Merge branch 'devel' of github.com:Araq/Nimrod into seq_toString

56 files changed, 3104 insertions, 1488 deletions

diff --git a/compiler/ast.nim b/compiler/ast.nim
index cd002eef1..0652bd3e7 100644
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -62,7 +62,7 @@ type
     nkTripleStrLit,       # a triple string literal """
     nkNilLit,             # the nil literal
                           # end of atoms
-    nkMetaNode,           # difficult to explain; represents itself
+    nkMetaNode_Obsolete,  # difficult to explain; represents itself
                           # (used for macros)
     nkDotCall,            # used to temporarily flag a nkCall node; 
                           # this is used
@@ -188,6 +188,10 @@ type
     nkStmtListType,       # a statement list ending in a type; for macros
     nkBlockType,          # a statement block ending in a type; for macros
                           # types as syntactic trees:
+
+    nkWith,               # distinct with `foo`
+    nkWithout,            # distinct without `foo`
+    
     nkTypeOfExpr,         # type(1+2)
     nkObjectTy,           # object body
     nkTupleTy,            # tuple body
@@ -382,6 +386,10 @@ type
       # sons[0]: type of containing object or tuple
       # sons[1]: field type
       # .n: nkDotExpr storing the field name
+    
+static:
+  # remind us when TTypeKind stops to fit in a single 64-bit word
+  assert TTypeKind.high.ord <= 63
 
 const
   tyPureObject* = tyTuple
@@ -394,7 +402,7 @@ const
                     tyUserTypeClass, tyUserTypeClassInst,
                     tyAnd, tyOr, tyNot, tyAnything}
 
-  tyMetaTypes* = {tyGenericParam, tyTypeDesc, tyStatic, tyExpr} + tyTypeClasses
+  tyMetaTypes* = {tyGenericParam, tyTypeDesc, tyExpr} + tyTypeClasses
  
 type
   TTypeKinds* = set[TTypeKind]
@@ -409,12 +417,14 @@ type
                 # efficiency
     nfTransf,   # node has been transformed
     nfSem       # node has been checked for semantics
-    nfDelegate  # the call can use a delegator
+    nfDotField  # the call can use a dot operator
+    nfDotSetter # the call can use a setter dot operarator
+    nfExplicitCall # x.y() was used instead of x.y
     nfExprCall  # this is an attempt to call a regular expression
     nfIsRef     # this node is a 'ref' node; used for the VM
-
+ 
   TNodeFlags* = set[TNodeFlag]
-  TTypeFlag* = enum   # keep below 32 for efficiency reasons (now: 23)
+  TTypeFlag* = enum   # keep below 32 for efficiency reasons (now: 28)
     tfVarargs,        # procedure has C styled varargs
     tfNoSideEffect,   # procedure type does not allow side effects
     tfFinal,          # is the object final?
@@ -426,8 +436,11 @@ type
     tfFromGeneric,    # type is an instantiation of a generic; this is needed
                       # because for instantiations of objects, structural
                       # type equality has to be used
-    tfUnresolved,     # marks unresolved typedesc params: e.g.
+    tfUnresolved,     # marks unresolved typedesc/static params: e.g.
                       # proc foo(T: typedesc, list: seq[T]): var T
+                      # proc foo(L: static[int]): array[L, int]
+                      # can be attached to ranges to indicate that the range
+                      # depends on unresolved static params.
     tfRetType,        # marks return types in proc (used to detect type classes 
                       # used as return types for return type inference)
     tfCapturesEnv,    # whether proc really captures some environment
@@ -443,9 +456,16 @@ type
     tfHasMeta,        # type contains "wildcard" sub-types such as generic params
                       # or other type classes
     tfHasGCedMem,     # type contains GC'ed memory
+    tfPacked
     tfHasStatic
     tfGenericTypeParam
     tfImplicitTypeParam
+    tfWildcard        # consider a proc like foo[T, I](x: Type[T, I])
+                      # T and I here can bind to both typedesc and static types
+                      # before this is determined, we'll consider them to be a
+                      # wildcard type.
+    tfGuarded         # guarded pointer
+    tfBorrowDot       # distinct type borrows '.'
 
   TTypeFlags* = set[TTypeFlag]
 
@@ -467,7 +487,8 @@ type
     skResult,             # special 'result' variable
     skProc,               # a proc
     skMethod,             # a method
-    skIterator,           # an iterator
+    skIterator,           # an inline iterator
+    skClosureIterator,    # a resumable closure iterator
     skConverter,          # a type converter
     skMacro,              # a macro
     skTemplate,           # a template; currently also misused for user-defined
@@ -479,12 +500,15 @@ type
     skStub,               # symbol is a stub and not yet loaded from the ROD
                           # file (it is loaded on demand, which may
                           # mean: never)
+    skPackage             # symbol is a package (used for canonicalization)
   TSymKinds* = set[TSymKind]
 
 const
-  routineKinds* = {skProc, skMethod, skIterator, skConverter,
-    skMacro, skTemplate}
+  routineKinds* = {skProc, skMethod, skIterator, skClosureIterator,
+                   skConverter, skMacro, skTemplate}
   tfIncompleteStruct* = tfVarargs
+  tfUncheckedArray* = tfVarargs
+  tfUnion* = tfNoSideEffect
   skError* = skUnknown
   
   # type flags that are essential for type equality:
@@ -687,7 +711,7 @@ type
   TSym* {.acyclic.} = object of TIdObj
     # proc and type instantiations are cached in the generic symbol
     case kind*: TSymKind
-    of skType:
+    of skType, skGenericParam:
       typeInstCache*: seq[PType]
       typScope*: PScope
     of routineKinds:
@@ -812,13 +836,16 @@ type
     counter*: int
     data*: TObjectSeq
 
+  TImplication* = enum
+    impUnknown, impNo, impYes
+
 # BUGFIX: a module is overloadable so that a proc can have the
 # same name as an imported module. This is necessary because of
 # the poor naming choices in the standard library.
 
 const 
-  OverloadableSyms* = {skProc, skMethod, skIterator, skConverter,
-    skModule, skTemplate, skMacro}
+  OverloadableSyms* = {skProc, skMethod, skIterator, skClosureIterator,
+    skConverter, skModule, skTemplate, skMacro}
 
   GenericTypes*: TTypeKinds = {tyGenericInvokation, tyGenericBody, 
     tyGenericParam}
@@ -840,10 +867,12 @@ const
                                     tyTuple, tySequence}
   NilableTypes*: TTypeKinds = {tyPointer, tyCString, tyRef, tyPtr, tySequence,
     tyProc, tyString, tyError}
-  ExportableSymKinds* = {skVar, skConst, skProc, skMethod, skType, skIterator, 
+  ExportableSymKinds* = {skVar, skConst, skProc, skMethod, skType,
+    skIterator, skClosureIterator,
     skMacro, skTemplate, skConverter, skEnumField, skLet, skStub}
   PersistentNodeFlags*: TNodeFlags = {nfBase2, nfBase8, nfBase16,
-                                      nfAllConst, nfDelegate, nfIsRef}
+                                      nfDotSetter, nfDotField,
+                                      nfAllConst,nfIsRef}
   namePos* = 0
   patternPos* = 1    # empty except for term rewriting macros
   genericParamsPos* = 2
@@ -857,6 +886,7 @@ const
   nkCallKinds* = {nkCall, nkInfix, nkPrefix, nkPostfix,
                   nkCommand, nkCallStrLit, nkHiddenCallConv}
 
+  nkLiterals* = {nkCharLit..nkTripleStrLit}
   nkLambdaKinds* = {nkLambda, nkDo}
   declarativeDefs* = {nkProcDef, nkMethodDef, nkIteratorDef, nkConverterDef}
   procDefs* = nkLambdaKinds + declarativeDefs
@@ -865,7 +895,10 @@ const
   nkStrKinds* = {nkStrLit..nkTripleStrLit}
 
   skLocalVars* = {skVar, skLet, skForVar, skParam, skResult}
-  skProcKinds* = {skProc, skTemplate, skMacro, skIterator, skMethod, skConverter}
+  skProcKinds* = {skProc, skTemplate, skMacro, skIterator, skClosureIterator,
+                  skMethod, skConverter}
+
+  skIterators* = {skIterator, skClosureIterator}
 
   lfFullExternalName* = lfParamCopy # \
     # only used when 'gCmd == cmdPretty': Indicates that the symbol has been
@@ -946,7 +979,9 @@ var emptyNode* = newNode(nkEmpty)
 # There is a single empty node that is shared! Do not overwrite it!
 
 proc isMetaType*(t: PType): bool =
-  return t.kind in tyMetaTypes or tfHasMeta in t.flags
+  return t.kind in tyMetaTypes or
+         (t.kind == tyStatic and t.n == nil) or
+         tfHasMeta in t.flags
 
 proc linkTo*(t: PType, s: PSym): PType {.discardable.} =
   t.sym = s
@@ -1008,7 +1043,7 @@ proc discardSons(father: PNode) =
   father.sons = nil
 
 when defined(useNodeIds):
-  const nodeIdToDebug = 612777 # 612794
+  const nodeIdToDebug* = 482228 # 612794
   #612840 # 612905 # 614635 # 614637 # 614641
   # 423408
   #429107 # 430443 # 441048 # 441090 # 441153
@@ -1044,6 +1079,10 @@ proc newStrNode(kind: TNodeKind, strVal: string): PNode =
   result = newNode(kind)
   result.strVal = strVal
 
+proc withInfo*(n: PNode, info: TLineInfo): PNode =
+  n.info = info
+  return n
+
 proc newIdentNode(ident: PIdent, info: TLineInfo): PNode = 
   result = newNode(nkIdent)
   result.ident = ident
@@ -1105,10 +1144,6 @@ proc newNodeIT(kind: TNodeKind, info: TLineInfo, typ: PType): PNode =
   result.info = info
   result.typ = typ
 
-proc newMetaNodeIT*(tree: PNode, info: TLineInfo, typ: PType): PNode =
-  result = newNodeIT(nkMetaNode, info, typ)
-  result.add(tree)
-
 var emptyParams = newNode(nkFormalParams)
 emptyParams.addSon(emptyNode)
 
@@ -1276,7 +1311,7 @@ proc skipTypes*(t: PType, kinds: TTypeKinds): PType =
 proc propagateToOwner*(owner, elem: PType) =
   const HaveTheirOwnEmpty = {tySequence, tySet}
   owner.flags = owner.flags + (elem.flags * {tfHasShared, tfHasMeta,
-                                             tfHasStatic, tfHasGCedMem})
+                                             tfHasGCedMem})
   if tfNotNil in elem.flags:
     if owner.kind in {tyGenericInst, tyGenericBody, tyGenericInvokation}:
       owner.flags.incl tfNotNil
@@ -1290,12 +1325,9 @@ proc propagateToOwner*(owner, elem: PType) =
   if tfShared in elem.flags:
     owner.flags.incl tfHasShared
 
-  if elem.kind in tyMetaTypes:
+  if elem.isMetaType:
     owner.flags.incl tfHasMeta
 
-  if elem.kind == tyStatic:
-    owner.flags.incl tfHasStatic
-
   if elem.kind in {tyString, tyRef, tySequence} or
       elem.kind == tyProc and elem.callConv == ccClosure:
     owner.flags.incl tfHasGCedMem
@@ -1475,8 +1507,7 @@ proc originatingModule*(s: PSym): PSym =
   while result.kind != skModule: result = result.owner
 
 proc isRoutine*(s: PSym): bool {.inline.} =
-  result = s.kind in {skProc, skTemplate, skMacro, skIterator, skMethod,
-                      skConverter}
+  result = s.kind in skProcKinds
 
 proc hasPattern*(s: PSym): bool {.inline.} =
   result = isRoutine(s) and s.ast.sons[patternPos].kind != nkEmpty
@@ -1484,6 +1515,9 @@ proc hasPattern*(s: PSym): bool {.inline.} =
 iterator items*(n: PNode): PNode =
   for i in 0.. <n.len: yield n.sons[i]
 
+iterator pairs*(n: PNode): tuple[i: int, n: PNode] =
+  for i in 0.. <n.len: yield (i, n.sons[i])
+
 proc isAtom*(n: PNode): bool {.inline.} =
   result = n.kind >= nkNone and n.kind <= nkNilLit
 
diff --git a/compiler/astalgo.nim b/compiler/astalgo.nim
index 64c1b717c..36dd7f562 100644
--- a/compiler/astalgo.nim
+++ b/compiler/astalgo.nim
@@ -50,7 +50,7 @@ proc strTableGet*(t: TStrTable, name: PIdent): PSym
 type 
   TTabIter*{.final.} = object # consider all fields here private
     h*: THash                 # current hash
-  
+
 proc initTabIter*(ti: var TTabIter, tab: TStrTable): PSym
 proc nextIter*(ti: var TTabIter, tab: TStrTable): PSym
   # usage:
@@ -157,6 +157,12 @@ proc leValue*(a, b: PNode): bool =
     #InternalError(a.info, "leValue")
     discard
 
+proc weakLeValue*(a, b: PNode): TImplication =
+  if a.kind notin nkLiterals or b.kind notin nkLiterals:
+    result = impUnknown
+  else:
+    result = if leValue(a, b): impYes else: impNo
+
 proc lookupInRecord(n: PNode, field: PIdent): PSym = 
   result = nil
   case n.kind
@@ -337,7 +343,10 @@ proc treeToYamlAux(n: PNode, marker: var TIntSet, indent: int,
         appf(result, ",$N$1\"floatVal\": $2", 
             [istr, toRope(n.floatVal.toStrMaxPrecision)])
       of nkStrLit..nkTripleStrLit: 
-        appf(result, ",$N$1\"strVal\": $2", [istr, makeYamlString(n.strVal)])
+        if n.strVal.isNil:
+          appf(result, ",$N$1\"strVal\": null", [istr])
+        else:
+          appf(result, ",$N$1\"strVal\": $2", [istr, makeYamlString(n.strVal)])
       of nkSym: 
         appf(result, ",$N$1\"sym\": $2", 
              [istr, symToYamlAux(n.sym, marker, indent + 2, maxRecDepth)])
@@ -407,7 +416,10 @@ proc debugTree(n: PNode, indent: int, maxRecDepth: int): PRope =
         appf(result, ",$N$1\"floatVal\": $2", 
             [istr, toRope(n.floatVal.toStrMaxPrecision)])
       of nkStrLit..nkTripleStrLit: 
-        appf(result, ",$N$1\"strVal\": $2", [istr, makeYamlString(n.strVal)])
+        if n.strVal.isNil:
+          appf(result, ",$N$1\"strVal\": null", [istr])
+        else:
+          appf(result, ",$N$1\"strVal\": $2", [istr, makeYamlString(n.strVal)])
       of nkSym: 
         appf(result, ",$N$1\"sym\": $2_$3", 
             [istr, toRope(n.sym.name.s), toRope(n.sym.id)])
diff --git a/compiler/c2nim/cparse.nim b/compiler/c2nim/cparse.nim
index ffab05788..52d50ca39 100644
--- a/compiler/c2nim/cparse.nim
+++ b/compiler/c2nim/cparse.nim
@@ -540,7 +540,7 @@ proc typeAtom(p: var TParser): PNode =
       if p.tok.s == "unsigned":
         isUnsigned = true
       elif p.tok.s == "signed" or p.tok.s == "int":
-        nil
+        discard
       else:
         add(x, p.tok.s)
       getTok(p, nil)
@@ -624,10 +624,11 @@ proc parseTypeSuffix(p: var TParser, typ: PNode): PNode =
         # array type:
         result = newNodeP(nkBracketExpr, p)
         addSon(result, newIdentNodeP("array", p))
-        var r = newNodeP(nkRange, p)
-        addSon(r, newIntNodeP(nkIntLit, 0, p))
-        addSon(r, newBinary("-", index, newIntNodeP(nkIntLit, 1, p), p))
-        addSon(result, r)
+        #var r = newNodeP(nkRange, p)
+        #addSon(r, newIntNodeP(nkIntLit, 0, p))
+        #addSon(r, newBinary("-", index, newIntNodeP(nkIntLit, 1, p), p))
+        #addSon(result, r)
+        addSon(result, index)
         addSon(result, tmp)
       else:
         # pointer type:
@@ -681,11 +682,6 @@ proc parseField(p: var TParser, kind: TNodeKind): PNode =
     else: result = mangledIdent(p.tok.s, p)
     getTok(p, result)
 
-proc takeOnlyFirstField(p: TParser, isUnion: bool): bool =
-  # if we generate an interface to a header file, *all* fields can be 
-  # generated:
-  result = isUnion and p.options.header.len == 0
-
 proc parseStructBody(p: var TParser, isUnion: bool,
                      kind: TNodeKind = nkRecList): PNode =
   result = newNodeP(kind, p)
@@ -698,8 +694,7 @@ proc parseStructBody(p: var TParser, isUnion: bool,
       var i = parseField(p, kind)
       t = parseTypeSuffix(p, t)
       addSon(def, i, t, ast.emptyNode)
-      if not takeOnlyFirstField(p, isUnion) or sonsLen(result) < 1: 
-        addSon(result, def)
+      addSon(result, def)
       if p.tok.xkind != pxComma: break
       getTok(p, def)
     eat(p, pxSemicolon, lastSon(result))
@@ -710,11 +705,12 @@ proc structPragmas(p: TParser, name: PNode, origName: string): PNode =
   result = newNodeP(nkPragmaExpr, p)
   addSon(result, exportSym(p, name, origName))
   var pragmas = newNodeP(nkPragma, p)
-  addSon(pragmas, newIdentNodeP("pure", p), newIdentNodeP("final", p))
+  #addSon(pragmas, newIdentNodeP("pure", p), newIdentNodeP("final", p))
   if p.options.header.len > 0:
     addSon(pragmas, newIdentStrLitPair("importc", origName, p),
                     newIdentStrLitPair("header", p.options.header, p))
-  addSon(result, pragmas)
+  if pragmas.len > 0: addSon(result, pragmas)
+  else: addSon(result, ast.emptyNode)
 
 proc enumPragmas(p: TParser, name: PNode): PNode =
   result = newNodeP(nkPragmaExpr, p)
@@ -726,9 +722,13 @@ proc enumPragmas(p: TParser, name: PNode): PNode =
   addSon(pragmas, e)
   addSon(result, pragmas)
 
-proc parseStruct(p: var TParser, isUnion: bool): PNode = 
+proc parseStruct(p: var TParser, isUnion: bool): PNode =
   result = newNodeP(nkObjectTy, p)
-  addSon(result, ast.emptyNode, ast.emptyNode) # no pragmas, no inheritance 
+  var pragmas = ast.emptyNode
+  if isUnion:
+    pragmas = newNodeP(nkPragma, p)
+    addSon(pragmas, newIdentNodeP("union", p))
+  addSon(result, pragmas, ast.emptyNode) # no inheritance 
   if p.tok.xkind == pxCurlyLe:
     addSon(result, parseStructBody(p, isUnion))
   else: 
@@ -746,7 +746,7 @@ proc directDeclarator(p: var TParser, a: PNode, ident: ptr PNode): PNode =
       result = declarator(p, a, ident)
       eat(p, pxParRi, result)
   else:
-    nil
+    discard
   return parseTypeSuffix(p, a)
 
 proc declarator(p: var TParser, a: PNode, ident: ptr PNode): PNode =
@@ -1165,7 +1165,7 @@ proc enumSpecifier(p: var TParser): PNode =
 
 proc setBaseFlags(n: PNode, base: TNumericalBase) = 
   case base
-  of base10: nil
+  of base10: discard
   of base2: incl(n.flags, nfBase2)
   of base8: incl(n.flags, nfBase8)
   of base16: incl(n.flags, nfBase16)
@@ -1279,7 +1279,8 @@ proc leftBindingPower(p : var TParser, tok : ref TToken) : int =
   of pxComma:
     return 10
     # throw == 20
-  of pxAsgn, pxPlusAsgn, pxMinusAsgn, pxStarAsgn, pxSlashAsgn, pxModAsgn, pxShlAsgn, pxShrAsgn, pxAmpAsgn, pxHatAsgn, pxBarAsgn:
+  of pxAsgn, pxPlusAsgn, pxMinusAsgn, pxStarAsgn, pxSlashAsgn, pxModAsgn, 
+     pxShlAsgn, pxShrAsgn, pxAmpAsgn, pxHatAsgn, pxBarAsgn:
     return 30
   of pxConditional:
     return 40
@@ -1686,7 +1687,7 @@ proc switchStatement(p: var TParser): PNode =
       break
     of "case", "default":
       break
-    else: nil
+    else: discard
     addSon(result, statement(p))
   if sonsLen(result) == 0:
     # translate empty statement list to Nimrod's ``nil`` statement
diff --git a/compiler/c2nim/cpp.nim b/compiler/c2nim/cpp.nim
index 1707b75db..84b4c4dfb 100644
--- a/compiler/c2nim/cpp.nim
+++ b/compiler/c2nim/cpp.nim
@@ -103,7 +103,7 @@ proc parseDefBody(p: var TParser, m: var TMacro, params: seq[string]) =
       m.body.add(tok)
     of pxDirConc: 
       # just ignore this token: this implements token merging correctly
-      nil
+      discard
     else:
       m.body.add(p.tok)
     # we do not want macro expansion here:
@@ -166,7 +166,7 @@ proc parseStmtList(p: var TParser): PNode =
     of pxDirectiveParLe, pxDirective: 
       case p.tok.s
       of "else", "endif", "elif": break
-    else: nil
+    else: discard
     addSon(result, statement(p))
   
 proc eatEndif(p: var TParser) =
diff --git a/compiler/canonicalizer.nim b/compiler/canonicalizer.nim
new file mode 100644
index 000000000..3bc4eb029
--- /dev/null
+++ b/compiler/canonicalizer.nim
@@ -0,0 +1,416 @@
+#
+#
+#           The Nimrod Compiler
+#        (c) Copyright 2014 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## This module implements the canonalization for the various caching mechanisms.
+
+import strutils, db_sqlite, md5
+
+var db: TDbConn
+
+# We *hash* the relevant information into 128 bit hashes. This should be good
+# enough to prevent any collisions.
+
+type
+  TUid = distinct MD5Digest
+
+# For name mangling we encode these hashes via a variant of base64 (called
+# 'base64a') and prepend the *primary* identifier to ease the debugging pain.
+# So a signature like:
+#
+#   proc gABI(c: PCtx; n: PNode; opc: TOpcode; a, b: TRegister; imm: BiggestInt)
+#
+# is mangled into:
+#   gABI_MTdmOWY5MTQ1MDcyNGQ3ZA
+#
+# This is a good compromise between correctness and brevity. ;-)
+
+const

+  cb64 = [
+    "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N",
+    "O", "P", "Q", "R", "S", "T" "U", "V", "W", "X", "Y", "Z", 
+    "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", 
+    "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", 
+    "0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
+    "_A", "_B"]

+

+proc toBase64a(s: cstring, len: int): string =

+  ## encodes `s` into base64 representation. After `lineLen` characters, a 

+  ## `newline` is added.

+  result = newStringOfCap(((len + 2) div 3) * 4)

+  var i = 0

+  while i < s.len - 2:

+    let a = ord(s[i])

+    let b = ord(s[i+1])

+    let c = ord(s[i+2])

+    result.add cb64[a shr 2]

+    result.add cb64[((a and 3) shl 4) or ((b and 0xF0) shr 4)]

+    result.add cb64[((b and 0x0F) shl 2) or ((c and 0xC0) shr 6)]

+    result.add cb64[c and 0x3F]

+    inc(i, 3)

+  if i < s.len-1:

+    let a = ord(s[i])

+    let b = ord(s[i+1])

+    result.add cb64[a shr 2]

+    result.add cb64[((a and 3) shl 4) or ((b and 0xF0) shr 4)]

+    result.add cb64[((b and 0x0F) shl 2)]

+  elif i < s.len:

+    let a = ord(s[i])

+    result.add cb64[a shr 2]

+    result.add cb64[(a and 3) shl 4]

+
+proc toBase64a(u: TUid): string = toBase64a(cast[cstring](u), sizeof(u))
+
+proc `&=`(c: var MD5Context, s: string) = md5Update(c, s, s.len)
+
+proc hashSym(c: var MD5Context, s: PSym) =
+  if sfAnon in s.flags or s.kind == skGenericParam:
+    c &= ":anon"
+  else:
+    var it = s.owner
+    while it != nil: 
+      hashSym(c, it)
+      c &= "."
+      it = s.owner
+    c &= s.name.s
+
+proc hashTree(c: var MD5Context, n: PNode) =
+  if n == nil:
+    c &= "\255"
+    return
+  var k = n.kind
+  md5Update(c, cast[cstring](addr(k)), 1)
+  # we really must not hash line information. 'n.typ' is debatable but
+  # shouldn't be necessary for now and avoids potential infinite recursions.
+  case n.kind
+  of nkEmpty, nkNilLit, nkType: discard
+  of nkIdent:
+    c &= n.ident.s
+  of nkSym:
+    hashSym(c, n.sym)
+  of nkCharLit..nkUInt64Lit:
+    var v = n.intVal
+    md5Update(c, cast[cstring](addr(v)), sizeof(v))
+  of nkFloatLit..nkFloat64Lit:
+    var v = n.floatVal
+    md5Update(c, cast[cstring](addr(v)), sizeof(v))
+  of nkStrLit..nkTripleStrLit:
+    c &= n.strVal
+  else:
+    for i in 0.. <n.len: hashTree(c, n.sons[i])
+
+proc hashType(c: var MD5Context, t: PType) =
+  # modelled after 'typeToString'
+  if t == nil: 
+    c &= "\254"
+    return
+
+  var k = t.kind
+  md5Update(c, cast[cstring](addr(k)), 1)
+  
+  if t.sym != nil and sfAnon notin t.sym.flags:
+    # t.n for literals, but not for e.g. objects!
+    if t.kind in {tyFloat, tyInt}: c.hashNode(t.n)
+    c.hashSym(t.sym)
+    
+  case t.kind
+  of tyGenericBody, tyGenericInst, tyGenericInvokation:
+    for i in countup(0, sonsLen(t) -1 -ord(t.kind != tyGenericInvokation)):
+      c.hashType t.sons[i]
+  of tyUserTypeClass:
+    internalAssert t.sym != nil and t.sym.owner != nil
+    c &= t.sym.owner.name.s
+  of tyUserTypeClassInst:
+    let body = t.base
+    c.hashSym body.sym
+    for i in countup(1, sonsLen(t) - 2):
+      c.hashType t.sons[i]
+  of tyFromExpr, tyFieldAccessor:
+    c.hashTree(t.n)
+  of tyArrayConstr:
+    c.hashTree(t.sons[0].n)
+    c.hashType(t.sons[1])
+  of tyTuple: 
+    if t.n != nil:
+      assert(sonsLen(t.n) == sonsLen(t))
+      for i in countup(0, sonsLen(t.n) - 1): 
+        assert(t.n.sons[i].kind == nkSym)
+        c &= t.n.sons[i].sym.name.s
+        c &= ":"
+        c.hashType(t.sons[i])
+        c &= ","
+    else:
+      for i in countup(0, sonsLen(t) - 1): c.hashType t.sons[i]
+  of tyRange:
+    c.hashTree(t.n)
+    c.hashType(t.sons[0])
+  of tyProc:
+    c &= (if tfIterator in t.flags: "iterator " else: "proc ")
+    for i in 0.. <t.len: c.hashType(t.sons[i])
+    md5Update(c, cast[cstring](addr(t.callConv)), 1)
+
+    if tfNoSideEffect in t.flags: c &= ".noSideEffect"
+    if tfThread in t.flags: c &= ".thread"
+  else:
+    for i in 0.. <t.len: c.hashType(t.sons[i])
+  if tfShared in t.flags: c &= "shared"
+  if tfNotNil in t.flags: c &= "not nil"
+
+proc canonConst(n: PNode): TUid =
+  var c: MD5Context
+  md5Init(c)
+  c.hashTree(n)
+  c.hashType(n.typ)
+  md5Final(c, MD5Digest(result))
+
+proc canonSym(s: PSym): TUid =
+  var c: MD5Context
+  md5Init(c)
+  c.hashSym(s)
+  md5Final(c, MD5Digest(result))
+
+proc pushType(w: PRodWriter, t: PType) =
+  # check so that the stack does not grow too large:
+  if iiTableGet(w.index.tab, t.id) == InvalidKey:
+    w.tstack.add(t)
+
+proc pushSym(w: PRodWriter, s: PSym) =
+  # check so that the stack does not grow too large:
+  if iiTableGet(w.index.tab, s.id) == InvalidKey:
+    w.sstack.add(s)
+
+proc encodeNode(w: PRodWriter, fInfo: TLineInfo, n: PNode, 
+                result: var string) = 
+  if n == nil: 
+    # nil nodes have to be stored too:
+    result.add("()")
+    return
+  result.add('(')
+  encodeVInt(ord(n.kind), result) 
+  # we do not write comments for now
+  # Line information takes easily 20% or more of the filesize! Therefore we
+  # omit line information if it is the same as the father's line information:
+  if fInfo.fileIndex != n.info.fileIndex: 
+    result.add('?')
+    encodeVInt(n.info.col, result)
+    result.add(',')
+    encodeVInt(n.info.line, result)
+    result.add(',')
+    encodeVInt(fileIdx(w, toFilename(n.info)), result)
+  elif fInfo.line != n.info.line:
+    result.add('?')
+    encodeVInt(n.info.col, result)
+    result.add(',')
+    encodeVInt(n.info.line, result)
+  elif fInfo.col != n.info.col:
+    result.add('?')
+    encodeVInt(n.info.col, result)
+  var f = n.flags * PersistentNodeFlags
+  if f != {}: 
+    result.add('$')
+    encodeVInt(cast[int32](f), result)
+  if n.typ != nil:
+    result.add('^')
+    encodeVInt(n.typ.id, result)
+    pushType(w, n.typ)
+  case n.kind
+  of nkCharLit..nkInt64Lit: 
+    if n.intVal != 0:
+      result.add('!')
+      encodeVBiggestInt(n.intVal, result)
+  of nkFloatLit..nkFloat64Lit: 
+    if n.floatVal != 0.0: 
+      result.add('!')
+      encodeStr($n.floatVal, result)
+  of nkStrLit..nkTripleStrLit:
+    if n.strVal != "": 
+      result.add('!')
+      encodeStr(n.strVal, result)
+  of nkIdent:
+    result.add('!')
+    encodeStr(n.ident.s, result)
+  of nkSym:
+    result.add('!')
+    encodeVInt(n.sym.id, result)
+    pushSym(w, n.sym)
+  else:
+    for i in countup(0, sonsLen(n) - 1): 
+      encodeNode(w, n.info, n.sons[i], result)
+  add(result, ')')
+
+proc encodeLoc(w: PRodWriter, loc: TLoc, result: var string) = 
+  var oldLen = result.len
+  result.add('<')
+  if loc.k != low(loc.k): encodeVInt(ord(loc.k), result)
+  if loc.s != low(loc.s): 
+    add(result, '*')
+    encodeVInt(ord(loc.s), result)
+  if loc.flags != {}: 
+    add(result, '$')
+    encodeVInt(cast[int32](loc.flags), result)
+  if loc.t != nil:
+    add(result, '^')
+    encodeVInt(cast[int32](loc.t.id), result)
+    pushType(w, loc.t)
+  if loc.r != nil: 
+    add(result, '!')
+    encodeStr(ropeToStr(loc.r), result)
+  if loc.a != 0: 
+    add(result, '?')
+    encodeVInt(loc.a, result)
+  if oldLen + 1 == result.len:
+    # no data was necessary, so remove the '<' again:
+    setLen(result, oldLen)
+  else:
+    add(result, '>')
+  
+proc encodeType(w: PRodWriter, t: PType, result: var string) = 
+  if t == nil: 
+    # nil nodes have to be stored too:
+    result.add("[]")
+    return
+  # we need no surrounding [] here because the type is in a line of its own
+  if t.kind == tyForward: internalError("encodeType: tyForward")
+  # for the new rodfile viewer we use a preceeding [ so that the data section
+  # can easily be disambiguated:
+  add(result, '[')
+  encodeVInt(ord(t.kind), result)
+  add(result, '+')
+  encodeVInt(t.id, result)
+  if t.n != nil: 
+    encodeNode(w, unknownLineInfo(), t.n, result)
+  if t.flags != {}: 
+    add(result, '$')
+    encodeVInt(cast[int32](t.flags), result)
+  if t.callConv != low(t.callConv): 
+    add(result, '?')
+    encodeVInt(ord(t.callConv), result)
+  if t.owner != nil: 
+    add(result, '*')
+    encodeVInt(t.owner.id, result)
+    pushSym(w, t.owner)
+  if t.sym != nil: 
+    add(result, '&')
+    encodeVInt(t.sym.id, result)
+    pushSym(w, t.sym)
+  if t.size != - 1: 
+    add(result, '/')
+    encodeVBiggestInt(t.size, result)
+  if t.align != 2: 
+    add(result, '=')
+    encodeVInt(t.align, result)
+  encodeLoc(w, t.loc, result)
+  for i in countup(0, sonsLen(t) - 1): 
+    if t.sons[i] == nil: 
+      add(result, "^()")
+    else: 
+      add(result, '^') 
+      encodeVInt(t.sons[i].id, result)
+      pushType(w, t.sons[i])
+
+proc encodeLib(w: PRodWriter, lib: PLib, info: TLineInfo, result: var string) = 
+  add(result, '|')
+  encodeVInt(ord(lib.kind), result)
+  add(result, '|')
+  encodeStr(ropeToStr(lib.name), result)
+  add(result, '|')
+  encodeNode(w, info, lib.path, result)
+
+proc encodeSym(w: PRodWriter, s: PSym, result: var string) =
+  if s == nil:
+    # nil nodes have to be stored too:
+    result.add("{}")
+    return
+  # we need no surrounding {} here because the symbol is in a line of its own
+  encodeVInt(ord(s.kind), result)
+  result.add('+')
+  encodeVInt(s.id, result)
+  result.add('&')
+  encodeStr(s.name.s, result)
+  if s.typ != nil:
+    result.add('^')
+    encodeVInt(s.typ.id, result)
+    pushType(w, s.typ)
+  result.add('?')
+  if s.info.col != -1'i16: encodeVInt(s.info.col, result)
+  result.add(',')
+  if s.info.line != -1'i16: encodeVInt(s.info.line, result)
+  result.add(',')
+  encodeVInt(fileIdx(w, toFilename(s.info)), result)
+  if s.owner != nil:
+    result.add('*')
+    encodeVInt(s.owner.id, result)
+    pushSym(w, s.owner)
+  if s.flags != {}:
+    result.add('$')
+    encodeVInt(cast[int32](s.flags), result)
+  if s.magic != mNone:
+    result.add('@')
+    encodeVInt(ord(s.magic), result)
+  if s.options != w.options: 
+    result.add('!')
+    encodeVInt(cast[int32](s.options), result)
+  if s.position != 0: 
+    result.add('%')
+    encodeVInt(s.position, result)
+  if s.offset != - 1:
+    result.add('`')
+    encodeVInt(s.offset, result)
+  encodeLoc(w, s.loc, result)
+  if s.annex != nil: encodeLib(w, s.annex, s.info, result)
+  if s.constraint != nil:
+    add(result, '#')
+    encodeNode(w, unknownLineInfo(), s.constraint, result)
+  # lazy loading will soon reload the ast lazily, so the ast needs to be
+  # the last entry of a symbol:
+  if s.ast != nil:
+    # we used to attempt to save space here by only storing a dummy AST if
+    # it is not necessary, but Nimrod's heavy compile-time evaluation features
+    # make that unfeasible nowadays:
+    encodeNode(w, s.info, s.ast, result)
+
+
+proc createDb() =
+  db.exec(sql"""
+    create table if not exists Module(
+      id integer primary key,
+      name varchar(256) not null,
+      fullpath varchar(256) not null,
+      interfHash varchar(256) not null,
+      fullHash varchar(256) not null,
+      
+      created timestamp not null default (DATETIME('now')),
+    );""")
+
+  db.exec(sql"""
+    create table if not exists Symbol(
+      id integer primary key,
+      module integer not null,
+      name varchar(max) not null,
+      data varchar(max) not null,
+      created timestamp not null default (DATETIME('now')),
+
+      foreign key (module) references module(id)
+    );""")
+    
+  db.exec(sql"""
+    create table if not exists Type(
+      id integer primary key,
+      module integer not null,
+      name varchar(max) not null,
+      data varchar(max) not null,
+      created timestamp not null default (DATETIME('now')),
+
+      foreign key (module) references module(id)
+    );""")
+
+
+  #db.exec(sql"""
+  #  --create unique index if not exists TsstNameIx on TestResult(name);
+  #  """, [])
+
diff --git a/compiler/ccgexprs.nim b/compiler/ccgexprs.nim
index 01f23850b..a4ba412a4 100644
--- a/compiler/ccgexprs.nim
+++ b/compiler/ccgexprs.nim
@@ -593,7 +593,7 @@ proc unaryArith(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
 
 proc genDeref(p: BProc, e: PNode, d: var TLoc) =
   var a: TLoc
-  if mapType(e.sons[0].typ) == ctArray:
+  if mapType(e.sons[0].typ) in {ctArray, ctPtrToArray}:
     # XXX the amount of hacks for C's arrays is incredible, maybe we should
     # simply wrap them in a struct? --> Losing auto vectorization then?
     expr(p, e.sons[0], d)
@@ -736,7 +736,7 @@ proc genArrayElem(p: BProc, e: PNode, d: var TLoc) =
   var ty = skipTypes(skipTypes(a.t, abstractVarRange), abstractPtrs)
   var first = intLiteral(firstOrd(ty))
   # emit range check:
-  if (optBoundsCheck in p.options):
+  if optBoundsCheck in p.options and tfUncheckedArray notin ty.flags:
     if not isConstExpr(e.sons[1]):
       # semantic pass has already checked for const index expressions
       if firstOrd(ty) == 0:
@@ -1803,7 +1803,7 @@ proc expr(p: BProc, n: PNode, d: var TLoc) =
       else:
         genProc(p.module, sym)
       putLocIntoDest(p, d, sym.loc)
-    of skProc, skConverter, skIterator:
+    of skProc, skConverter, skIterators:
       genProc(p.module, sym)
       if sym.loc.r == nil or sym.loc.t == nil:
         internalError(n.info, "expr: proc not init " & sym.name.s)
@@ -1915,7 +1915,6 @@ proc expr(p: BProc, n: PNode, d: var TLoc) =
       internalError(n.info, "expr: proc not init " & sym.name.s)
     putLocIntoDest(p, d, sym.loc)
   of nkClosure: genClosure(p, n, d)
-  of nkMetaNode: expr(p, n.sons[0], d)
 
   of nkEmpty: discard
   of nkWhileStmt: genWhileStmt(p, n)
diff --git a/compiler/ccgmerge.nim b/compiler/ccgmerge.nim
index 5b04f1358..2d27257ce 100644
--- a/compiler/ccgmerge.nim
+++ b/compiler/ccgmerge.nim
@@ -145,33 +145,6 @@ proc atEndMark(buf: cstring, pos: int): bool =
   while s < NimMergeEndMark.len and buf[pos+s] == NimMergeEndMark[s]: inc s
   result = s == NimMergeEndMark.len
 
-when false:
-  proc readVerbatimSection(L: var TBaseLexer): PRope = 
-    var pos = L.bufpos
-    var buf = L.buf
-    result = newMutableRope(30_000)
-    while true:
-      case buf[pos]
-      of CR:
-        pos = nimlexbase.HandleCR(L, pos)
-        buf = L.buf
-        result.data.add(tnl)
-      of LF:
-        pos = nimlexbase.HandleLF(L, pos)
-        buf = L.buf
-        result.data.add(tnl)
-      of '\0':
-        InternalError("ccgmerge: expected: " & NimMergeEndMark)
-        break
-      else: 
-        if atEndMark(buf, pos):
-          inc pos, NimMergeEndMark.len
-          break
-        result.data.add(buf[pos])
-        inc pos
-    L.bufpos = pos
-    freezeMutableRope(result)
-
 proc readVerbatimSection(L: var TBaseLexer): PRope = 
   var pos = L.bufpos
   var buf = L.buf
diff --git a/compiler/ccgstmts.nim b/compiler/ccgstmts.nim
index af0d657f1..990153fc7 100644
--- a/compiler/ccgstmts.nim
+++ b/compiler/ccgstmts.nim
@@ -65,6 +65,7 @@ proc startBlock(p: BProc, start: TFormatStr = "{$n",
   setLen(p.blocks, result + 1)
   p.blocks[result].id = p.labels
   p.blocks[result].nestedTryStmts = p.nestedTryStmts.len.int16
+  p.blocks[result].nestedExceptStmts = p.inExceptBlock.int16
 
 proc assignLabel(b: var TBlock): PRope {.inline.} =
   b.label = con("LA", b.id.toRope)
@@ -260,37 +261,57 @@ proc genIf(p: BProc, n: PNode, d: var TLoc) =
     else: internalError(n.info, "genIf()")
   if sonsLen(n) > 1: fixLabel(p, lend)
 
-proc blockLeaveActions(p: BProc, howMany: int) = 
-  var L = p.nestedTryStmts.len
-  # danger of endless recursion! we workaround this here by a temp stack
+
+proc blockLeaveActions(p: BProc, howManyTrys, howManyExcepts: int) = 
+  # Called by return and break stmts.
+  # Deals with issues faced when jumping out of try/except/finally stmts,
+
   var stack: seq[PNode]
-  newSeq(stack, howMany)
-  for i in countup(1, howMany): 
-    stack[i-1] = p.nestedTryStmts[L-i]
-  setLen(p.nestedTryStmts, L-howMany)
+  newSeq(stack, 0)
   
   var alreadyPoppedCnt = p.inExceptBlock
-  for tryStmt in items(stack):
+  for i in countup(1, howManyTrys):
+
     if gCmd != cmdCompileToCpp:
+      # Pop safe points generated by try
       if alreadyPoppedCnt > 0:
         dec alreadyPoppedCnt
       else:
         linefmt(p, cpsStmts, "#popSafePoint();$n")
+
+    # Pop this try-stmt of the list of nested trys
+    # so we don't infinite recurse on it in the next step.
+    var tryStmt = p.nestedTryStmts.pop
+    stack.add(tryStmt)
+
+    # Find finally-stmt for this try-stmt
+    # and generate a copy of its sons
     var finallyStmt = lastSon(tryStmt)
     if finallyStmt.kind == nkFinally: 
       genStmts(p, finallyStmt.sons[0])
+
   # push old elements again:
-  for i in countdown(howMany-1, 0): 
+  for i in countdown(howManyTrys-1, 0): 
     p.nestedTryStmts.add(stack[i])
+
   if gCmd != cmdCompileToCpp:
-    for i in countdown(p.inExceptBlock-1, 0):
+    # Pop exceptions that was handled by the
+    # except-blocks we are in
+    for i in countdown(howManyExcepts-1, 0):
       linefmt(p, cpsStmts, "#popCurrentException();$n")
 
 proc genReturnStmt(p: BProc, t: PNode) =
   p.beforeRetNeeded = true
   genLineDir(p, t)
   if (t.sons[0].kind != nkEmpty): genStmts(p, t.sons[0])
-  blockLeaveActions(p, min(1, p.nestedTryStmts.len))
+  blockLeaveActions(p, 
+    howManyTrys    = p.nestedTryStmts.len,
+    howManyExcepts = p.inExceptBlock)
+  if (p.finallySafePoints.len > 0):
+    # If we're in a finally block, and we came here by exception
+    # consume it before we return.
+    var safePoint = p.finallySafePoints[p.finallySafePoints.len-1]
+    linefmt(p, cpsStmts, "if ($1.status != 0) #popCurrentException();$n", safePoint)    
   lineFF(p, cpsStmts, "goto BeforeRet;$n", "br label %BeforeRet$n", [])
 
 proc genComputedGoto(p: BProc; n: PNode) =
@@ -450,7 +471,9 @@ proc genBreakStmt(p: BProc, t: PNode) =
     if idx < 0 or not p.blocks[idx].isLoop:
       internalError(t.info, "no loop to break")
   let label = assignLabel(p.blocks[idx])
-  blockLeaveActions(p, p.nestedTryStmts.len - p.blocks[idx].nestedTryStmts)
+  blockLeaveActions(p, 
+    p.nestedTryStmts.len - p.blocks[idx].nestedTryStmts,
+    p.inExceptBlock - p.blocks[idx].nestedExceptStmts)
   genLineDir(p, t)
   lineF(p, cpsStmts, "goto $1;$n", [label])
 
@@ -827,7 +850,9 @@ proc genTry(p: BProc, t: PNode, d: var TLoc) =
   discard pop(p.nestedTryStmts)
   endBlock(p) # end of else block
   if i < length and t.sons[i].kind == nkFinally:
+    p.finallySafePoints.add(safePoint)
     exprBlock(p, t.sons[i].sons[0], d)
+    discard pop(p.finallySafePoints)
   linefmt(p, cpsStmts, "if ($1.status != 0) #reraiseException();$n", safePoint)
 
 proc genAsmOrEmitStmt(p: BProc, t: PNode, isAsmStmt=false): PRope =
@@ -838,7 +863,7 @@ proc genAsmOrEmitStmt(p: BProc, t: PNode, isAsmStmt=false): PRope =
       res.add(t.sons[i].strVal)
     of nkSym:
       var sym = t.sons[i].sym
-      if sym.kind in {skProc, skIterator, skMethod}: 
+      if sym.kind in {skProc, skIterator, skClosureIterator, skMethod}:
         var a: TLoc
         initLocExpr(p, t.sons[i], a)
         res.add(rdLoc(a).ropeToStr)
diff --git a/compiler/ccgtypes.nim b/compiler/ccgtypes.nim
index c92c15fa9..319d6a5c5 100644
--- a/compiler/ccgtypes.nim
+++ b/compiler/ccgtypes.nim
@@ -69,7 +69,7 @@ proc mangleName(s: PSym): PRope =
   if result == nil: 
     if gCmd == cmdCompileToLLVM: 
       case s.kind
-      of skProc, skMethod, skConverter, skConst, skIterator: 
+      of skProc, skMethod, skConverter, skConst, skIterators:
         result = ~"@"
       of skVar, skForVar, skResult, skLet: 
         if sfGlobal in s.flags: result = ~"@"
@@ -185,7 +185,7 @@ proc mapType(typ: PType): TCTypeKind =
   of tyPtr, tyVar, tyRef:
     var base = skipTypes(typ.sons[0], typedescInst)
     case base.kind
-    of tyOpenArray, tyArrayConstr, tyArray, tyVarargs: result = ctArray
+    of tyOpenArray, tyArrayConstr, tyArray, tyVarargs: result = ctPtrToArray
     else: result = ctPtr
   of tyPointer: result = ctPtr
   of tySequence: result = ctNimSeq
@@ -376,10 +376,13 @@ proc getTypePre(m: BModule, typ: PType): PRope =
   else: 
     result = getSimpleTypeDesc(m, typ)
     if result == nil: result = cacheGetType(m.typeCache, typ)
-  
+
+proc structOrUnion(t: PType): PRope =
+  (if tfUnion in t.flags: toRope("union") else: toRope("struct"))
+
 proc getForwardStructFormat(): string = 
-  if gCmd == cmdCompileToCpp: result = "struct $1;$n"
-  else: result = "typedef struct $1 $1;$n"
+  if gCmd == cmdCompileToCpp: result = "$1 $2;$n"
+  else: result = "typedef $1 $2 $2;$n"
   
 proc getTypeForward(m: BModule, typ: PType): PRope = 
   result = cacheGetType(m.forwTypeCache, typ)
@@ -390,7 +393,8 @@ proc getTypeForward(m: BModule, typ: PType): PRope =
   of tySequence, tyTuple, tyObject: 
     result = getTypeName(typ)
     if not isImportedType(typ): 
-      appf(m.s[cfsForwardTypes], getForwardStructFormat(), [result])
+      appf(m.s[cfsForwardTypes], getForwardStructFormat(),
+          [structOrUnion(typ), result])
     idTablePut(m.forwTypeCache, typ, result)
   else: internalError("getTypeForward(" & $typ.kind & ')')
   
@@ -445,7 +449,12 @@ proc genRecordFieldsAux(m: BModule, n: PNode,
     if accessExpr != nil: ae = ropef("$1.$2", [accessExpr, sname])
     else: ae = sname
     fillLoc(field.loc, locField, field.typ, ae, OnUnknown)
-    appf(result, "$1 $2;$n", [getTypeDescAux(m, field.loc.t, check), sname])
+    let fieldType = field.loc.t
+    if fieldType.kind == tyArray and tfUncheckedArray in fieldType.flags:
+      appf(result, "$1 $2[SEQ_DECL_SIZE];$n",
+          [getTypeDescAux(m, fieldType.elemType, check), sname])
+    else:
+      appf(result, "$1 $2;$n", [getTypeDescAux(m, fieldType, check), sname])
   else: internalError(n.info, "genRecordFieldsAux()")
   
 proc getRecordFields(m: BModule, typ: PType, check: var TIntSet): PRope = 
@@ -455,23 +464,33 @@ proc getRecordDesc(m: BModule, typ: PType, name: PRope,
                    check: var TIntSet): PRope = 
   # declare the record:
   var hasField = false
+
+  var attribute: PRope =
+    if tfPacked in typ.flags: toRope(CC[ccompiler].packedPragma)
+    else: nil
+
+  result = ropecg(m, CC[ccompiler].structStmtFmt, 
+    [structOrUnion(typ), name, attribute])
+
   if typ.kind == tyObject: 
+
     if typ.sons[0] == nil: 
       if (typ.sym != nil and sfPure in typ.sym.flags) or tfFinal in typ.flags: 
-        result = ropecg(m, "struct $1 {$n", [name])
+        appcg(m, result, " {$n", [])
       else: 
-        result = ropecg(m, "struct $1 {$n#TNimType* m_type;$n", [name])
+        appcg(m, result, " {$n#TNimType* m_type;$n", [name, attribute])
         hasField = true
     elif gCmd == cmdCompileToCpp: 
-      result = ropecg(m, "struct $1 : public $2 {$n", 
-                      [name, getTypeDescAux(m, typ.sons[0], check)])
+      appcg(m, result, " : public $1 {$n", 
+                      [getTypeDescAux(m, typ.sons[0], check)])
       hasField = true
     else: 
-      result = ropecg(m, "struct $1 {$n  $2 Sup;$n", 
-                      [name, getTypeDescAux(m, typ.sons[0], check)])
+      appcg(m, result, " {$n  $1 Sup;$n", 
+                      [getTypeDescAux(m, typ.sons[0], check)])
       hasField = true
   else: 
-    result = ropef("struct $1 {$n", [name])
+    appf(result, " {$n", [name])
+
   var desc = getRecordFields(m, typ, check)
   if (desc == nil) and not hasField: 
     appf(result, "char dummy;$n", [])
@@ -480,8 +499,8 @@ proc getRecordDesc(m: BModule, typ: PType, name: PRope,
   app(result, "};" & tnl)
 
 proc getTupleDesc(m: BModule, typ: PType, name: PRope, 
-                  check: var TIntSet): PRope = 
-  result = ropef("struct $1 {$n", [name])
+                  check: var TIntSet): PRope =
+  result = ropef("$1 $2 {$n", [structOrUnion(typ), name])
   var desc: PRope = nil
   for i in countup(0, sonsLen(typ) - 1): 
     appf(desc, "$1 Field$2;$n", 
@@ -557,7 +576,8 @@ proc getTypeDescAux(m: BModule, typ: PType, check: var TIntSet): PRope =
     if result == nil: 
       result = getTypeName(t)
       if not isImportedType(t): 
-        appf(m.s[cfsForwardTypes], getForwardStructFormat(), [result])
+        appf(m.s[cfsForwardTypes], getForwardStructFormat(),
+            [structOrUnion(t), result])
       idTablePut(m.forwTypeCache, t, result)
     assert(cacheGetType(m.typeCache, t) == nil)
     idTablePut(m.typeCache, t, con(result, "*"))
@@ -588,7 +608,8 @@ proc getTypeDescAux(m: BModule, typ: PType, check: var TIntSet): PRope =
     if result == nil: 
       result = getTypeName(t)
       if not isImportedType(t): 
-        appf(m.s[cfsForwardTypes], getForwardStructFormat(), [result])
+        appf(m.s[cfsForwardTypes], getForwardStructFormat(),
+           [structOrUnion(t), result])
       idTablePut(m.forwTypeCache, t, result)
     idTablePut(m.typeCache, t, result) # always call for sideeffects:
     if t.kind != tyTuple: recdesc = getRecordDesc(m, t, result, check)
diff --git a/compiler/ccgutils.nim b/compiler/ccgutils.nim
index 1129ecbef..1d8f0158b 100644
--- a/compiler/ccgutils.nim
+++ b/compiler/ccgutils.nim
@@ -87,9 +87,10 @@ proc getUniqueType*(key: PType): PType =
       gCanonicalTypes[k] = key
       result = key
   of tyTypeDesc, tyTypeClasses, tyGenericParam,
-     tyFromExpr, tyStatic, tyFieldAccessor:
+     tyFromExpr, tyFieldAccessor:
     internalError("GetUniqueType")
-  of tyGenericInst, tyDistinct, tyOrdinal, tyMutable, tyConst, tyIter:
+  of tyGenericInst, tyDistinct, tyOrdinal, tyMutable,
+     tyConst, tyIter, tyStatic:
     result = getUniqueType(lastSon(key))
   of tyArrayConstr, tyGenericInvokation, tyGenericBody,
      tyOpenArray, tyArray, tySet, tyRange, tyTuple,
@@ -130,7 +131,6 @@ proc getUniqueType*(key: PType): PType =
       idTablePut(gTypeTable[k], key, key)
       result = key
   of tyProc:
-    # tyVar is not 100% correct, but would speeds things up a little:
     if key.callConv != ccClosure:
       result = key
     else:
diff --git a/compiler/cgen.nim b/compiler/cgen.nim
index 5057ae558..683aed069 100644
--- a/compiler/cgen.nim
+++ b/compiler/cgen.nim
@@ -705,7 +705,7 @@ proc cgsym(m: BModule, name: string): PRope =
   var sym = magicsys.getCompilerProc(name)
   if sym != nil: 
     case sym.kind
-    of skProc, skMethod, skConverter, skIterator: genProc(m, sym)
+    of skProc, skMethod, skConverter, skIterators: genProc(m, sym)
     of skVar, skResult, skLet: genVarPrototype(m, sym)
     of skType: discard getTypeDesc(m, sym.typ)
     else: internalError("cgsym: " & name)
@@ -761,6 +761,8 @@ proc genProcAux(m: BModule, prc: PSym) =
   var returnStmt: PRope = nil
   assert(prc.ast != nil)
   if sfPure notin prc.flags and prc.typ.sons[0] != nil:
+    if resultPos >= prc.ast.len:
+      internalError(prc.info, "proc has no result symbol")
     var res = prc.ast.sons[resultPos].sym # get result symbol
     if not isInvalidReturnType(prc.typ.sons[0]):
       if sfNoInit in prc.flags: incl(res.flags, sfNoInit)
@@ -962,8 +964,8 @@ proc genMainProc(m: BModule) =
     NimMainBody =
       "N_CDECL(void, NimMain)(void) {$N" &
         "\tPreMain();$N" &
-        "$1$N" &
-      "}$N"
+        "$1" &
+      "}$N$N"
 
     PosixNimMain =
       "int cmdCount;$N" &
@@ -977,20 +979,20 @@ proc genMainProc(m: BModule) =
         "\tcmdCount = argc;$N" &
         "\tgEnv = env;$N" &
         MainProcsWithResult &
-      "}$N"
+      "}$N$N"
   
     StandaloneCMain =
       "int main(void) {$N" &
         MainProcs &
         "\treturn 0;$N" &
-      "}$N"
+      "}$N$N"
     
     WinNimMain = NimMainBody
     
     WinCMain = "N_STDCALL(int, WinMain)(HINSTANCE hCurInstance, $N" &
       "                        HINSTANCE hPrevInstance, $N" &
       "                        LPSTR lpCmdLine, int nCmdShow) {$N" &
-      MainProcsWithResult & "}$N"
+      MainProcsWithResult & "}$N$N"
   
     WinNimDllMain = "N_LIB_EXPORT " & NimMainBody
 
@@ -998,14 +1000,14 @@ proc genMainProc(m: BModule) =
       "BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fwdreason, $N" &
       "                    LPVOID lpvReserved) {$N" &
       "\tif(fwdreason == DLL_PROCESS_ATTACH) {$N" & MainProcs & "}$N" &
-      "\treturn 1;$N}$N"
+      "\treturn 1;$N}$N$N"
 
     PosixNimDllMain = WinNimDllMain
     
     PosixCDllMain =
       "void NIM_POSIX_INIT NimMainInit(void) {$N" &
         MainProcs &
-      "}$N"
+      "}$N$N"
 
   var nimMain, otherMain: TFormatStr
   if platform.targetOS == osWindows and
@@ -1034,7 +1036,7 @@ proc genMainProc(m: BModule) =
                               platform.targetOS == osStandalone: "".toRope
                             else: ropecg(m, "\t#initStackBottom();$N")
   inc(m.labels)
-  appcg(m, m.s[cfsProcs], "void PreMain() {$N" & PreMainBody & "}$N", [
+  appcg(m, m.s[cfsProcs], "void PreMain() {$N" & PreMainBody & "}$N$N", [
     mainDatInit, initStackBottomCall, gBreakpoints, otherModsInit])
 
   appcg(m, m.s[cfsProcs], nimMain, [mainModInit, toRope(m.labels)])
@@ -1042,8 +1044,10 @@ proc genMainProc(m: BModule) =
     appcg(m, m.s[cfsProcs], otherMain, [])
 
 proc getSomeInitName(m: PSym, suffix: string): PRope =
+  assert m.kind == skModule
+  assert m.owner.kind == skPackage
   if {sfSystemModule, sfMainModule} * m.flags == {}:
-    result = m.info.toFullPath.getPackageName.mangle.toRope
+    result = m.owner.name.s.mangle.toRope
   result.app m.name.s
   result.app suffix
   
@@ -1188,7 +1192,7 @@ proc nullify[T](arr: var T) =
   for i in low(arr)..high(arr):
     arr[i] = nil
 
-proc resetModule*(m: var BModule) =
+proc resetModule*(m: BModule) =
   # between two compilations in CAAS mode, we can throw
   # away all the data that was written to disk
   initLinkedList(m.headerFiles)
diff --git a/compiler/cgendata.nim b/compiler/cgendata.nim
index 9cd2c0d87..e7d818556 100644
--- a/compiler/cgendata.nim
+++ b/compiler/cgendata.nim
@@ -41,7 +41,8 @@ type
     ctInt, ctInt8, ctInt16, ctInt32, ctInt64,
     ctFloat, ctFloat32, ctFloat64, ctFloat128,
     ctUInt, ctUInt8, ctUInt16, ctUInt32, ctUInt64,
-    ctArray, ctStruct, ctPtr, ctNimStr, ctNimSeq, ctProc, ctCString
+    ctArray, ctPtrToArray, ctStruct, ctPtr, ctNimStr, ctNimSeq, ctProc,
+    ctCString
   TCFileSections* = array[TCFileSection, PRope] # represents a generated C file
   TCProcSection* = enum       # the sections a generated C proc consists of
     cpsLocals,                # section of local variables for C proc
@@ -57,17 +58,20 @@ type
     sections*: TCProcSections # the code beloging
     isLoop*: bool             # whether block is a loop
     nestedTryStmts*: int16    # how many try statements is it nested into
+    nestedExceptStmts*: int16 # how many except statements is it nested into
     frameLen*: int16
   
   TCProc{.final.} = object    # represents C proc that is currently generated
     prc*: PSym                # the Nimrod proc that this C proc belongs to
     beforeRetNeeded*: bool    # true iff 'BeforeRet' label for proc is needed
     threadVarAccessed*: bool  # true if the proc already accessed some threadvar
-    nestedTryStmts*: seq[PNode] # in how many nested try statements we are
-                                # (the vars must be volatile then)
+    nestedTryStmts*: seq[PNode]   # in how many nested try statements we are
+                                  # (the vars must be volatile then)
     inExceptBlock*: int       # are we currently inside an except block?
                               # leaving such scopes by raise or by return must
                               # execute any applicable finally blocks
+    finallySafePoints*: seq[PRope]  # For correctly cleaning up exceptions when
+                                    # using return in finally statements
     labels*: Natural          # for generating unique labels in the C proc
     blocks*: seq[TBlock]      # nested blocks
     breakIdx*: int            # the block that will be exited
@@ -140,8 +144,9 @@ proc newProc*(prc: PSym, module: BModule): BProc =
   else: result.options = gOptions
   newSeq(result.blocks, 1)
   result.nestedTryStmts = @[]
+  result.finallySafePoints = @[]
 
-iterator cgenModules*: var BModule =
+iterator cgenModules*: BModule =
   for i in 0..high(gModules):
     # ultimately, we are iterating over the file ids here.
     # some "files" won't have an associated cgen module (like stdin)
diff --git a/compiler/condsyms.nim b/compiler/condsyms.nim
index c79fda13e..ddf2075b4 100644
--- a/compiler/condsyms.nim
+++ b/compiler/condsyms.nim
@@ -47,6 +47,7 @@ proc initDefines*() =
   defineSymbol("nimeffects")
   defineSymbol("nimbabel")
   defineSymbol("nimcomputedgoto")
+  defineSymbol("nimunion")
   
   # add platform specific symbols:
   case targetCPU
diff --git a/compiler/docgen.nim b/compiler/docgen.nim
index 343f415b3..d8c439c9c 100644
--- a/compiler/docgen.nim
+++ b/compiler/docgen.nim
@@ -42,17 +42,23 @@ proc compilerMsgHandler(filename: string, line, col: int,
   of mwUnsupportedLanguage: k = warnLanguageXNotSupported
   globalError(newLineInfo(filename, line, col), k, arg)
 
+proc docgenFindFile(s: string): string {.procvar.} =
+  result = options.findFile(s)
+  if result.len == 0:
+    result = getCurrentDir() / s
+    if not existsFile(result): result = ""
+
 proc parseRst(text, filename: string,
               line, column: int, hasToc: var bool,
               rstOptions: TRstParseOptions): PRstNode =
   result = rstParse(text, filename, line, column, hasToc, rstOptions,
-                    options.findFile, compilerMsgHandler)
+                    docgenFindFile, compilerMsgHandler)
 
 proc newDocumentor*(filename: string, config: PStringTable): PDoc =
   new(result)
   initRstGenerator(result[], (if gCmd != cmdRst2tex: outHtml else: outLatex),
                    options.gConfigVars, filename, {roSupportRawDirective},
-                   options.findFile, compilerMsgHandler)
+                   docgenFindFile, compilerMsgHandler)
   result.id = 100
 
 proc dispA(dest: var PRope, xml, tex: string, args: openArray[PRope]) =
@@ -360,7 +366,7 @@ proc generateJson(d: PDoc, n: PNode, jArray: PJsonNode = nil): PJsonNode =
 proc genSection(d: PDoc, kind: TSymKind) =
   const sectionNames: array[skModule..skTemplate, string] = [
     "Imports", "Types", "Vars", "Lets", "Consts", "Vars", "Procs", "Methods",
-    "Iterators", "Converters", "Macros", "Templates"
+    "Iterators", "Iterators", "Converters", "Macros", "Templates"
   ]
   if d.section[kind] == nil: return
   var title = sectionNames[kind].toRope
diff --git a/compiler/evalffi.nim b/compiler/evalffi.nim
index 54be0ccb2..db78da714 100644
--- a/compiler/evalffi.nim
+++ b/compiler/evalffi.nim
@@ -151,7 +151,7 @@ proc getField(n: PNode; position: int): PSym =
   else: discard
 
 proc packObject(x: PNode, typ: PType, res: pointer) =
-  InternalAssert x.kind in {nkObjConstr, nkPar}
+  internalAssert x.kind in {nkObjConstr, nkPar}
   # compute the field's offsets:
   discard typ.getSize
   for i in countup(ord(x.kind == nkObjConstr), sonsLen(x) - 1):
diff --git a/compiler/extccomp.nim b/compiler/extccomp.nim
index 12761f1d4..f0e5dad11 100644
--- a/compiler/extccomp.nim
+++ b/compiler/extccomp.nim
@@ -16,7 +16,7 @@ import
 type 
   TSystemCC* = enum 
     ccNone, ccGcc, ccLLVM_Gcc, ccCLang, ccLcc, ccBcc, ccDmc, ccWcc, ccVcc, 
-    ccTcc, ccPcc, ccUcc, ccIcl, ccGpp
+    ccTcc, ccPcc, ccUcc, ccIcl
   TInfoCCProp* = enum         # properties of the C compiler:
     hasSwitchRange,           # CC allows ranges in switch statements (GNU C)
     hasComputedGoto,          # CC has computed goto (GNU C extension)
@@ -33,11 +33,12 @@ type
     optSpeed: string,    # the options for optimization for speed
     optSize: string,     # the options for optimization for size
     compilerExe: string, # the compiler's executable
+    cppCompiler: string, # name of the C++ compiler's executable (if supported)
     compileTmpl: string, # the compile command template
     buildGui: string,    # command to build a GUI application
     buildDll: string,    # command to build a shared library
     buildLib: string,    # command to build a static library
-    linkerExe: string,   # the linker's executable
+    linkerExe: string,   # the linker's executable (if not matching compiler's)
     linkTmpl: string,    # command to link files to produce an exe
     includeCmd: string,  # command to add an include dir
     linkDirCmd: string,  # command to add a lib dir
@@ -46,6 +47,8 @@ type
     pic: string,         # command for position independent code
                          # used on some platforms
     asmStmtFrmt: string, # format of ASM statement
+    structStmtFmt: string, # Format for struct statement
+    packedPragma: string,  # Attribute/pragma to make struct packed (1-byte aligned)
     props: TInfoCCProps] # properties of the C compiler
 
 
@@ -63,11 +66,12 @@ compiler gcc:
     optSpeed: " -O3 -ffast-math ",
     optSize: " -Os -ffast-math ",
     compilerExe: "gcc",
+    cppCompiler: "g++",
     compileTmpl: "-c $options $include -o $objfile $file",
     buildGui: " -mwindows",
     buildDll: " -shared",
     buildLib: "ar rcs $libfile $objfiles",
-    linkerExe: "gcc",
+    linkerExe: "",
     linkTmpl: "$buildgui $builddll -o $exefile $objfiles $options",
     includeCmd: " -I",
     linkDirCmd: " -L",
@@ -75,34 +79,25 @@ compiler gcc:
     debug: "",
     pic: "-fPIC",
     asmStmtFrmt: "asm($1);$n",
+    structStmtFmt: "$1 $3 $2 ", # struct|union [packed] $name
+    packedPragma: "__attribute__((__packed__))",
     props: {hasSwitchRange, hasComputedGoto, hasCpp, hasGcGuard, hasGnuAsm,
             hasNakedAttribute})
-    
-compiler gpp:
-  result = gcc()
-  
-  result.name = "gpp"
-  result.compilerExe = "g++"
-  result.linkerExe = "g++"  
-
-  result.buildDll = " -mdll" 
-  # XXX: Hmm, I'm keeping this from the previos version, 
-  # but my gcc doesn't even have such an option (is this mingw?)
 
 compiler llvmGcc:
   result = gcc()
   
   result.name = "llvm_gcc"
   result.compilerExe = "llvm-gcc"
+  result.cppCompiler = "llvm-g++"
   result.buildLib = "llvm-ar rcs $libfile $objfiles"
-  result.linkerExe = "llvm-gcc"
 
 compiler clang:
   result = llvmGcc()
 
   result.name = "clang"
   result.compilerExe = "clang"
-  result.linkerExe = "clang"
+  result.cppCompiler = "clang++"
 
 compiler vcc:
   result = (
@@ -111,6 +106,7 @@ compiler vcc:
     optSpeed: " /Ogityb2 /G7 /arch:SSE2 ",
     optSize: " /O1 /G7 ",
     compilerExe: "cl",
+    cppCompiler: "cl",
     compileTmpl: "/c $options $include /Fo$objfile $file",
     buildGui: " /link /SUBSYSTEM:WINDOWS ",
     buildDll: " /LD",
@@ -123,6 +119,8 @@ compiler vcc:
     debug: " /GZ /Zi ",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$3$n$1 $2",
+    packedPragma: "#pragma pack(1)",
     props: {hasCpp, hasAssume, hasNakedDeclspec})
 
 compiler icl:
@@ -131,7 +129,7 @@ compiler icl:
     result = vcc()
   else:
     result = gcc()
-
+    
   result.name = "icl"
   result.compilerExe = "icl"
   result.linkerExe = "icl"
@@ -143,6 +141,7 @@ compiler lcc:
     optSpeed: " -O -p6 ",
     optSize: " -O -p6 ",
     compilerExe: "lcc",
+    cppCompiler: "",
     compileTmpl: "$options $include -Fo$objfile $file",
     buildGui: " -subsystem windows",
     buildDll: " -dll",
@@ -155,6 +154,8 @@ compiler lcc:
     debug: " -g5 ",
     pic: "",
     asmStmtFrmt: "_asm{$n$1$n}$n",
+    structStmtFmt: "$1 $2",
+    packedPragma: "", # XXX: not supported yet
     props: {})
 
 compiler bcc:
@@ -164,6 +165,7 @@ compiler bcc:
     optSpeed: " -O2 -6 ",
     optSize: " -O1 -6 ",
     compilerExe: "bcc32",
+    cppCompiler: "",
     compileTmpl: "-c $options $include -o$objfile $file",
     buildGui: " -tW",
     buildDll: " -tWD",
@@ -176,6 +178,8 @@ compiler bcc:
     debug: "",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$1 $2",
+    packedPragma: "", # XXX: not supported yet
     props: {hasCpp})
 
 compiler dmc:
@@ -185,6 +189,7 @@ compiler dmc:
     optSpeed: " -ff -o -6 ",
     optSize: " -ff -o -6 ",
     compilerExe: "dmc",
+    cppCompiler: "",
     compileTmpl: "-c $options $include -o$objfile $file",
     buildGui: " -L/exet:nt/su:windows",
     buildDll: " -WD",
@@ -197,6 +202,8 @@ compiler dmc:
     debug: " -g ",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$3$n$1 $2",
+    packedPragma: "#pragma pack(1)",
     props: {hasCpp})
 
 compiler wcc:
@@ -206,6 +213,7 @@ compiler wcc:
     optSpeed: " -ox -on -6 -d0 -fp6 -zW ",
     optSize: "",
     compilerExe: "wcl386",
+    cppCompiler: "",
     compileTmpl: "-c $options $include -fo=$objfile $file",
     buildGui: " -bw",
     buildDll: " -bd",
@@ -218,6 +226,8 @@ compiler wcc:
     debug: " -d2 ",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$1 $2",
+    packedPragma: "", # XXX: not supported yet
     props: {hasCpp})
 
 compiler tcc:
@@ -227,6 +237,7 @@ compiler tcc:
     optSpeed: "",
     optSize: "",
     compilerExe: "tcc",
+    cppCompiler: "",
     compileTmpl: "-c $options $include -o $objfile $file",
     buildGui: "UNAVAILABLE!",
     buildDll: " -shared",
@@ -239,6 +250,8 @@ compiler tcc:
     debug: " -g ",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$1 $2",
+    packedPragma: "", # XXX: not supported yet
     props: {hasSwitchRange, hasComputedGoto})
 
 compiler pcc:
@@ -249,6 +262,7 @@ compiler pcc:
     optSpeed: " -Ox ",
     optSize: " -Os ",
     compilerExe: "cc",
+    cppCompiler: "",
     compileTmpl: "-c $options $include -Fo$objfile $file",
     buildGui: " -SUBSYSTEM:WINDOWS",
     buildDll: " -DLL",
@@ -261,6 +275,8 @@ compiler pcc:
     debug: " -Zi ",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$1 $2",
+    packedPragma: "", # XXX: not supported yet
     props: {})
 
 compiler ucc:
@@ -270,6 +286,7 @@ compiler ucc:
     optSpeed: " -O3 ",
     optSize: " -O1 ",
     compilerExe: "cc",
+    cppCompiler: "",
     compileTmpl: "-c $options $include -o $objfile $file",
     buildGui: "",
     buildDll: " -shared ",
@@ -282,6 +299,8 @@ compiler ucc:
     debug: "",
     pic: "",
     asmStmtFrmt: "__asm{$n$1$n}$n",
+    structStmtFmt: "$1 $2",
+    packedPragma: "", # XXX: not supported yet
     props: {})
 
 const 
@@ -297,8 +316,7 @@ const
     tcc(),
     pcc(),
     ucc(),
-    icl(),
-    gpp()]
+    icl()]
 
 const
   hExt* = ".h"
@@ -471,11 +489,21 @@ proc needsExeExt(): bool {.inline.} =
   result = (optGenScript in gGlobalOptions and targetOS == osWindows) or
                                        (platform.hostOS == osWindows)
 
+proc getCompilerExe(compiler: TSystemCC): string =
+  result = if gCmd == cmdCompileToCpp: CC[compiler].cppCompiler
+           else: CC[compiler].compilerExe
+  if result.len == 0:
+    rawMessage(errCompilerDoesntSupportTarget, CC[compiler].name)
+
+proc getLinkerExe(compiler: TSystemCC): string =
+  result = if CC[compiler].linkerExe.len > 0: CC[compiler].linkerExe
+           else: compiler.getCompilerExe
+
 proc getCompileCFileCmd*(cfilename: string, isExternal = false): string = 
   var c = cCompiler
   var options = cFileSpecificOptions(cfilename)
   var exe = getConfigVar(c, ".exe")
-  if exe.len == 0: exe = CC[c].compilerExe
+  if exe.len == 0: exe = c.getCompilerExe
   
   if needsExeExt(): exe = addFileExt(exe, "exe")
   if optGenDynLib in gGlobalOptions and
@@ -493,7 +521,7 @@ proc getCompileCFileCmd*(cfilename: string, isExternal = false): string =
     compilePattern = joinPath(ccompilerpath, exe)
   else: 
     includeCmd = ""
-    compilePattern = CC[c].compilerExe
+    compilePattern = c.getCompilerExe
   
   var cfile = if noAbsolutePaths(): extractFilename(cfilename) 
               else: cfilename
@@ -600,7 +628,7 @@ proc callCCompiler*(projectfile: string) =
       if optCompileOnly notin gGlobalOptions: execExternalProgram(linkCmd)
     else:
       var linkerExe = getConfigVar(c, ".linkerexe")
-      if len(linkerExe) == 0: linkerExe = CC[c].linkerExe
+      if len(linkerExe) == 0: linkerExe = c.getLinkerExe
       if needsExeExt(): linkerExe = addFileExt(linkerExe, "exe")
       if noAbsolutePaths(): linkCmd = quoteShell(linkerExe)
       else: linkCmd = quoteShell(joinPath(ccompilerpath, linkerExe))
diff --git a/compiler/guards.nim b/compiler/guards.nim
index 607bb074a..f475f5068 100644
--- a/compiler/guards.nim
+++ b/compiler/guards.nim
@@ -9,7 +9,7 @@
 
 ## This module implements the 'implies' relation for guards.
 
-import ast, astalgo, msgs, magicsys, nimsets, trees, types, renderer
+import ast, astalgo, msgs, magicsys, nimsets, trees, types, renderer, idents
 
 const
   someEq = {mEqI, mEqI64, mEqF64, mEqEnum, mEqCh, mEqB, mEqRef, mEqProc,
@@ -69,9 +69,23 @@ proc isLetLocation(m: PNode, isApprox: bool): bool =
 
 proc interestingCaseExpr*(m: PNode): bool = isLetLocation(m, true)
 
-proc swapArgs(fact: PNode, newOp: string, m: TMagic): PNode =
+proc getMagicOp(name: string, m: TMagic): PSym =
+  result = newSym(skProc, getIdent(name), nil, unknownLineInfo())
+  result.magic = m
+
+let
+  opLe = getMagicOp("<=", mLeI)
+  opLt = getMagicOp("<", mLtI)
+  opAnd = getMagicOp("and", mAnd)
+  opOr = getMagicOp("or", mOr)
+  opNot = getMagicOp("not", mNot)
+  opIsNil = getMagicOp("isnil", mIsNil)
+  opContains = getMagicOp("contains", mInSet)
+  opEq = getMagicOp("==", mEqI)
+
+proc swapArgs(fact: PNode, newOp: PSym): PNode =
   result = newNodeI(nkCall, fact.info, 3)
-  result.sons[0] = newSymNode(getSysMagic(newOp, m))
+  result.sons[0] = newSymNode(newOp)
   result.sons[1] = fact.sons[2]
   result.sons[2] = fact.sons[1]
 
@@ -82,9 +96,9 @@ proc neg(n: PNode): PNode =
     result = n.sons[1]
   of someLt:
     # not (a < b)  ==  a >= b  ==  b <= a
-    result = swapArgs(n, "<=", mLeI)
+    result = swapArgs(n, opLe)
   of someLe:
-    result = swapArgs(n, "<", mLtI)
+    result = swapArgs(n, opLt)
   of mInSet:
     if n.sons[1].kind != nkCurly: return nil
     let t = n.sons[2].typ.skipTypes(abstractInst)
@@ -110,7 +124,7 @@ proc neg(n: PNode): PNode =
       b = n.sons[2].neg
     if a != nil and b != nil:
       result = newNodeI(nkCall, n.info, 3)
-      result.sons[0] = newSymNode(getSysMagic("and", mAnd))
+      result.sons[0] = newSymNode(opAnd)
       result.sons[1] = a
       result.sons[2] = b
     elif a != nil:
@@ -120,12 +134,12 @@ proc neg(n: PNode): PNode =
   else:
     # leave  not (a == 4)  as it is
     result = newNodeI(nkCall, n.info, 2)
-    result.sons[0] = newSymNode(getSysMagic("not", mNot))
+    result.sons[0] = newSymNode(opNot)
     result.sons[1] = n
 
 proc buildIsNil(arg: PNode): PNode =
   result = newNodeI(nkCall, arg.info, 2)
-  result.sons[0] = newSymNode(getSysMagic("isNil", mIsNil))
+  result.sons[0] = newSymNode(opIsNil)
   result.sons[1] = arg
 
 proc usefulFact(n: PNode): PNode =
@@ -154,7 +168,7 @@ proc usefulFact(n: PNode): PNode =
       b = usefulFact(n.sons[2])
     if a != nil and b != nil:
       result = newNodeI(nkCall, n.info, 3)
-      result.sons[0] = newSymNode(getSysMagic("and", mAnd))
+      result.sons[0] = newSymNode(opAnd)
       result.sons[1] = a
       result.sons[2] = b
     elif a != nil:
@@ -177,7 +191,7 @@ proc usefulFact(n: PNode): PNode =
       b = usefulFact(n.sons[2]).neg
     if a != nil and b != nil:
       result = newNodeI(nkCall, n.info, 3)
-      result.sons[0] = newSymNode(getSysMagic("and", mAnd))
+      result.sons[0] = newSymNode(opAnd)
       result.sons[1] = a
       result.sons[2] = b
       result = result.neg
@@ -260,10 +274,6 @@ proc pred(n: PNode): PNode =
   else:
     result = n
 
-type
-  TImplication* = enum
-    impUnknown, impNo, impYes  
-
 proc impliesEq(fact, eq: PNode): TImplication =
   let (loc, val) = if isLocation(eq.sons[1]): (1, 2) else: (2, 1)
   
@@ -520,7 +530,7 @@ proc buildOf(it, loc: PNode): PNode =
   s.typ = settype(loc)
   for i in 0..it.len-2: s.sons[i] = it.sons[i]
   result = newNodeI(nkCall, it.info, 3)
-  result.sons[0] = newSymNode(getSysMagic("contains", mInSet))
+  result.sons[0] = newSymNode(opContains)
   result.sons[1] = s
   result.sons[2] = loc
 
@@ -532,20 +542,20 @@ proc buildElse(n: PNode): PNode =
     for j in 0..branch.len-2:
       s.add(branch.sons[j])
   result = newNodeI(nkCall, n.info, 3)
-  result.sons[0] = newSymNode(getSysMagic("contains", mInSet))
+  result.sons[0] = newSymNode(opContains)
   result.sons[1] = s
   result.sons[2] = n.sons[0]
 
 proc addDiscriminantFact*(m: var TModel, n: PNode) =
   var fact = newNodeI(nkCall, n.info, 3)
-  fact.sons[0] = newSymNode(getSysMagic("==", mEqI))
+  fact.sons[0] = newSymNode(opEq)
   fact.sons[1] = n.sons[0]
   fact.sons[2] = n.sons[1]
   m.add fact
 
 proc addAsgnFact*(m: var TModel, key, value: PNode) =
   var fact = newNodeI(nkCall, key.info, 3)
-  fact.sons[0] = newSymNode(getSysMagic("==", mEqI))
+  fact.sons[0] = newSymNode(opEq)
   fact.sons[1] = key
   fact.sons[2] = value
   m.add fact
diff --git a/compiler/idgen.nim b/compiler/idgen.nim
index c4f5f2a9e..d932e3d9d 100644
--- a/compiler/idgen.nim
+++ b/compiler/idgen.nim
@@ -19,7 +19,7 @@ const
 when debugIds:
   import intsets
   
-  var usedIds = InitIntSet()
+  var usedIds = initIntSet()
 
 proc registerID*(id: PIdObj) = 
   when debugIds: 
diff --git a/compiler/importer.nim b/compiler/importer.nim
index 078a90c98..7a73f2bbf 100644
--- a/compiler/importer.nim
+++ b/compiler/importer.nim
@@ -103,7 +103,7 @@ proc importSymbol(c: PContext, n: PNode, fromMod: PSym) =
       internalError(n.info, "importSymbol: 2")
     # for an enumeration we have to add all identifiers
     case s.kind
-    of skProc, skMethod, skIterator, skMacro, skTemplate, skConverter:
+    of skProcKinds:
       # for a overloadable syms add all overloaded routines
       var it: TIdentIter
       var e = initIdentIter(it, fromMod.tab, s.name)
diff --git a/compiler/jsgen.nim b/compiler/jsgen.nim
index c0fc4131a..0cbd4c364 100644
--- a/compiler/jsgen.nim
+++ b/compiler/jsgen.nim
@@ -275,11 +275,11 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["nimMax", "nimMax", "nimMax($1, $2)", "nimMax($1, $2)"], # MaxI64
     ["nimMin", "nimMin", "nimMin($1, $2)", "nimMin($1, $2)"], # MinF64
     ["nimMax", "nimMax", "nimMax($1, $2)", "nimMax($1, $2)"], # MaxF64
-    ["AddU", "AddU", "AddU($1, $2)", "AddU($1, $2)"], # AddU
-    ["SubU", "SubU", "SubU($1, $2)", "SubU($1, $2)"], # SubU
-    ["MulU", "MulU", "MulU($1, $2)", "MulU($1, $2)"], # MulU
-    ["DivU", "DivU", "DivU($1, $2)", "DivU($1, $2)"], # DivU
-    ["ModU", "ModU", "ModU($1, $2)", "ModU($1, $2)"], # ModU
+    ["addU", "addU", "addU($1, $2)", "addU($1, $2)"], # addU
+    ["subU", "subU", "subU($1, $2)", "subU($1, $2)"], # subU
+    ["mulU", "mulU", "mulU($1, $2)", "mulU($1, $2)"], # mulU
+    ["divU", "divU", "divU($1, $2)", "divU($1, $2)"], # divU
+    ["modU", "modU", "modU($1, $2)", "modU($1, $2)"], # modU
     ["", "", "($1 == $2)", "($1 == $2)"], # EqI
     ["", "", "($1 <= $2)", "($1 <= $2)"], # LeI
     ["", "", "($1 < $2)", "($1 < $2)"], # LtI
@@ -289,10 +289,10 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["", "", "($1 == $2)", "($1 == $2)"], # EqF64
     ["", "", "($1 <= $2)", "($1 <= $2)"], # LeF64
     ["", "", "($1 < $2)", "($1 < $2)"], # LtF64
-    ["LeU", "LeU", "LeU($1, $2)", "LeU($1, $2)"], # LeU
-    ["LtU", "LtU", "LtU($1, $2)", "LtU($1, $2)"], # LtU
-    ["LeU64", "LeU64", "LeU64($1, $2)", "LeU64($1, $2)"], # LeU64
-    ["LtU64", "LtU64", "LtU64($1, $2)", "LtU64($1, $2)"], # LtU64
+    ["leU", "leU", "leU($1, $2)", "leU($1, $2)"], # leU
+    ["ltU", "ltU", "ltU($1, $2)", "ltU($1, $2)"], # ltU
+    ["leU64", "leU64", "leU64($1, $2)", "leU64($1, $2)"], # leU64
+    ["ltU64", "ltU64", "ltU64($1, $2)", "ltU64($1, $2)"], # ltU64
     ["", "", "($1 == $2)", "($1 == $2)"], # EqEnum
     ["", "", "($1 <= $2)", "($1 <= $2)"], # LeEnum
     ["", "", "($1 < $2)", "($1 < $2)"], # LtEnum
@@ -309,10 +309,10 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["", "", "($1 == $2)", "($1 == $2)"], # EqCString
     ["", "", "($1 != $2)", "($1 != $2)"], # Xor
     ["", "", "($1 == $2)", "($1 == $2)"], # EqProc
-    ["NegInt", "", "NegInt($1)", "-($1)"], # UnaryMinusI
-    ["NegInt64", "", "NegInt64($1)", "-($1)"], # UnaryMinusI64
-    ["AbsInt", "", "AbsInt($1)", "Math.abs($1)"], # AbsI
-    ["AbsInt64", "", "AbsInt64($1)", "Math.abs($1)"], # AbsI64
+    ["negInt", "", "negInt($1)", "-($1)"], # UnaryMinusI
+    ["negInt64", "", "negInt64($1)", "-($1)"], # UnaryMinusI64
+    ["absInt", "", "absInt($1)", "Math.abs($1)"], # AbsI
+    ["absInt64", "", "absInt64($1)", "Math.abs($1)"], # AbsI64
     ["", "", "!($1)", "!($1)"], # Not
     ["", "", "+($1)", "+($1)"], # UnaryPlusI
     ["", "", "~($1)", "~($1)"], # BitnotI
@@ -327,9 +327,9 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["Ze16ToI64", "Ze16ToI64", "Ze16ToI64($1)", "Ze16ToI64($1)"], # mZe16ToI64
     ["Ze32ToI64", "Ze32ToI64", "Ze32ToI64($1)", "Ze32ToI64($1)"], # mZe32ToI64
     ["ZeIToI64", "ZeIToI64", "ZeIToI64($1)", "ZeIToI64($1)"], # mZeIToI64
-    ["ToU8", "ToU8", "ToU8($1)", "ToU8($1)"], # ToU8
-    ["ToU16", "ToU16", "ToU16($1)", "ToU16($1)"], # ToU16
-    ["ToU32", "ToU32", "ToU32($1)", "ToU32($1)"], # ToU32
+    ["toU8", "toU8", "toU8($1)", "toU8($1)"], # toU8
+    ["toU16", "toU16", "toU16($1)", "toU16($1)"], # toU16
+    ["toU32", "toU32", "toU32($1)", "toU32($1)"], # toU32
     ["", "", "$1", "$1"],     # ToFloat
     ["", "", "$1", "$1"],     # ToBiggestFloat
     ["", "", "Math.floor($1)", "Math.floor($1)"], # ToInt
@@ -375,11 +375,11 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["nimMax", "nimMax", "nimMax($1, $2)", "nimMax($1, $2)"], # MaxI64
     ["nimMin", "nimMin", "nimMin($1, $2)", "nimMin($1, $2)"], # MinF64
     ["nimMax", "nimMax", "nimMax($1, $2)", "nimMax($1, $2)"], # MaxF64
-    ["AddU", "AddU", "AddU($1, $2)", "AddU($1, $2)"], # AddU
-    ["SubU", "SubU", "SubU($1, $2)", "SubU($1, $2)"], # SubU
-    ["MulU", "MulU", "MulU($1, $2)", "MulU($1, $2)"], # MulU
-    ["DivU", "DivU", "DivU($1, $2)", "DivU($1, $2)"], # DivU
-    ["ModU", "ModU", "ModU($1, $2)", "ModU($1, $2)"], # ModU
+    ["addU", "addU", "addU($1, $2)", "addU($1, $2)"], # addU
+    ["subU", "subU", "subU($1, $2)", "subU($1, $2)"], # subU
+    ["mulU", "mulU", "mulU($1, $2)", "mulU($1, $2)"], # mulU
+    ["divU", "divU", "divU($1, $2)", "divU($1, $2)"], # divU
+    ["modU", "modU", "modU($1, $2)", "modU($1, $2)"], # modU
     ["", "", "($1 == $2)", "($1 == $2)"], # EqI
     ["", "", "($1 <= $2)", "($1 <= $2)"], # LeI
     ["", "", "($1 < $2)", "($1 < $2)"], # LtI
@@ -389,10 +389,10 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["", "", "($1 == $2)", "($1 == $2)"], # EqF64
     ["", "", "($1 <= $2)", "($1 <= $2)"], # LeF64
     ["", "", "($1 < $2)", "($1 < $2)"], # LtF64
-    ["LeU", "LeU", "LeU($1, $2)", "LeU($1, $2)"], # LeU
-    ["LtU", "LtU", "LtU($1, $2)", "LtU($1, $2)"], # LtU
-    ["LeU64", "LeU64", "LeU64($1, $2)", "LeU64($1, $2)"], # LeU64
-    ["LtU64", "LtU64", "LtU64($1, $2)", "LtU64($1, $2)"], # LtU64
+    ["leU", "leU", "leU($1, $2)", "leU($1, $2)"], # leU
+    ["ltU", "ltU", "ltU($1, $2)", "ltU($1, $2)"], # ltU
+    ["leU64", "leU64", "leU64($1, $2)", "leU64($1, $2)"], # leU64
+    ["ltU64", "ltU64", "ltU64($1, $2)", "ltU64($1, $2)"], # ltU64
     ["", "", "($1 == $2)", "($1 == $2)"], # EqEnum
     ["", "", "($1 <= $2)", "($1 <= $2)"], # LeEnum
     ["", "", "($1 < $2)", "($1 < $2)"], # LtEnum
@@ -409,10 +409,10 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["", "", "($1 == $2)", "($1 == $2)"], # EqCString
     ["", "", "($1 != $2)", "($1 != $2)"], # Xor
     ["", "", "($1 == $2)", "($1 == $2)"], # EqProc
-    ["NegInt", "", "NegInt($1)", "-($1)"], # UnaryMinusI
-    ["NegInt64", "", "NegInt64($1)", "-($1)"], # UnaryMinusI64
-    ["AbsInt", "", "AbsInt($1)", "Math.abs($1)"], # AbsI
-    ["AbsInt64", "", "AbsInt64($1)", "Math.abs($1)"], # AbsI64
+    ["negInt", "", "negInt($1)", "-($1)"], # UnaryMinusI
+    ["negInt64", "", "negInt64($1)", "-($1)"], # UnaryMinusI64
+    ["absInt", "", "absInt($1)", "Math.abs($1)"], # AbsI
+    ["absInt64", "", "absInt64($1)", "Math.abs($1)"], # AbsI64
     ["", "", "not ($1)", "not ($1)"], # Not
     ["", "", "+($1)", "+($1)"], # UnaryPlusI
     ["", "", "~($1)", "~($1)"], # BitnotI
@@ -427,9 +427,9 @@ const # magic checked op; magic unchecked op; checked op; unchecked op
     ["Ze16ToI64", "Ze16ToI64", "Ze16ToI64($1)", "Ze16ToI64($1)"], # mZe16ToI64
     ["Ze32ToI64", "Ze32ToI64", "Ze32ToI64($1)", "Ze32ToI64($1)"], # mZe32ToI64
     ["ZeIToI64", "ZeIToI64", "ZeIToI64($1)", "ZeIToI64($1)"], # mZeIToI64
-    ["ToU8", "ToU8", "ToU8($1)", "ToU8($1)"], # ToU8
-    ["ToU16", "ToU16", "ToU16($1)", "ToU16($1)"], # ToU16
-    ["ToU32", "ToU32", "ToU32($1)", "ToU32($1)"], # ToU32
+    ["toU8", "toU8", "toU8($1)", "toU8($1)"], # toU8
+    ["toU16", "toU16", "toU16($1)", "toU16($1)"], # toU16
+    ["toU32", "toU32", "toU32($1)", "toU32($1)"], # toU32
     ["", "", "$1", "$1"],     # ToFloat
     ["", "", "$1", "$1"],     # ToBiggestFloat
     ["", "", "Math.floor($1)", "Math.floor($1)"], # ToInt
@@ -812,8 +812,8 @@ proc genAsgnAux(p: PProc, x, y: PNode, noCopyNeeded: bool) =
     if needsNoCopy(y) or noCopyNeeded:
       appf(p.body, "$1 = $2;$n", [a.rdLoc, b.rdLoc])
     else:
-      useMagic(p, "NimCopy")
-      appf(p.body, "$1 = NimCopy($2, $3);$n",
+      useMagic(p, "nimCopy")
+      appf(p.body, "$1 = nimCopy($2, $3);$n",
            [a.res, b.res, genTypeInfo(p, y.typ)])
   of etyBaseIndex: 
     if a.typ != etyBaseIndex or b.typ != etyBaseIndex: 
@@ -1113,8 +1113,8 @@ proc createVar(p: PProc, typ: PType, indirect: bool): PRope =
     var length = int(lengthOrd(t))
     var e = elemType(t)
     if length > 32: 
-      useMagic(p, "ArrayConstr")
-      result = ropef("ArrayConstr($1, $2, $3)", [toRope(length), 
+      useMagic(p, "arrayConstr")
+      result = ropef("arrayConstr($1, $2, $3)", [toRope(length), 
           createVar(p, e, false), genTypeInfo(p, e)])
     else: 
       result = toRope("[")
@@ -1154,7 +1154,7 @@ proc createVar(p: PProc, typ: PType, indirect: bool): PRope =
 
 proc isIndirect(v: PSym): bool = 
   result = (sfAddrTaken in v.flags) and (mapType(v.typ) != etyObject) and
-    v.kind notin {skProc, skConverter, skMethod, skIterator}
+    v.kind notin {skProc, skConverter, skMethod, skIterator, skClosureIterator}
 
 proc genVarInit(p: PProc, v: PSym, n: PNode) = 
   var 
@@ -1171,8 +1171,8 @@ proc genVarInit(p: PProc, v: PSym, n: PNode) =
       if needsNoCopy(n): 
         s = a.res
       else: 
-        useMagic(p, "NimCopy")
-        s = ropef("NimCopy($1, $2)", [a.res, genTypeInfo(p, n.typ)])
+        useMagic(p, "nimCopy")
+        s = ropef("nimCopy($1, $2)", [a.res, genTypeInfo(p, n.typ)])
     of etyBaseIndex: 
       if (a.typ != etyBaseIndex): internalError(n.info, "genVarInit")
       if {sfAddrTaken, sfGlobal} * v.flags != {}: 
@@ -1600,7 +1600,6 @@ proc gen(p: PProc, n: PNode, r: var TCompRes) =
     if lfNoDecl in s.loc.flags or s.magic != mNone: discard
     elif not p.g.generatedSyms.containsOrIncl(s.id):
       app(p.locals, genProc(p, s))
-  of nkMetaNode: gen(p, n.sons[0], r)
   of nkType: r.res = genTypeInfo(p, n.typ)
   of nkStmtList, nkStmtListExpr:
     # this shows the distinction is nice for backends and should be kept
diff --git a/compiler/lambdalifting.nim b/compiler/lambdalifting.nim
index 3738f89b2..6da156ba6 100644
--- a/compiler/lambdalifting.nim
+++ b/compiler/lambdalifting.nim
@@ -11,7 +11,7 @@
 
 import 
   intsets, strutils, lists, options, ast, astalgo, trees, treetab, msgs, os, 
-  idents, renderer, types, magicsys, rodread
+  idents, renderer, types, magicsys, rodread, lowerings
 
 discard """
   The basic approach is that captured vars need to be put on the heap and
@@ -232,9 +232,9 @@ proc newOuterContext(fn: PSym, up: POuterContext = nil): POuterContext =
   initIdNodeTable(result.localsToAccess)
   initIdTable(result.localsToEnv)
   initIdTable(result.lambdasToEnv)
-  result.isIter = fn.kind == skIterator and fn.typ.callConv == ccClosure
+  result.isIter = fn.kind == skClosureIterator
   if result.isIter: initIterContext(result, fn)
-  
+
 proc newInnerContext(fn: PSym): PInnerContext =
   new(result)
   result.fn = fn
@@ -292,8 +292,7 @@ proc newCall(a, b: PSym): PNode =
   result.add newSymNode(b)
 
 proc isInnerProc(s, outerProc: PSym): bool {.inline.} =
-  result = (s.kind in {skProc, skMethod, skConverter} or
-            s.kind == skIterator and s.typ.callConv == ccClosure) and
+  result = s.kind in {skProc, skMethod, skConverter, skClosureIterator} and
            s.skipGenericOwner == outerProc
   #s.typ.callConv == ccClosure
 
@@ -357,7 +356,10 @@ proc captureVar(o: POuterContext, i: PInnerContext, local: PSym,
     # it's in some upper environment:
     access = indirectAccess(access, addDep(e, it, i.fn), info)
   access = indirectAccess(access, local, info)
-  incl(o.capturedVars, local.id)
+  if o.isIter:
+    if not containsOrIncl(o.capturedVars, local.id): addField(o.tup, local)
+  else:
+    incl(o.capturedVars, local.id)
   idNodeTablePut(i.localsToAccess, local, access)
 
 proc interestingVar(s: PSym): bool {.inline.} =
@@ -519,7 +521,7 @@ proc searchForInnerProcs(o: POuterContext, n: PNode) =
       else:
         internalError(it.info, "transformOuter")
   of nkProcDef, nkMethodDef, nkConverterDef, nkMacroDef, nkTemplateDef, 
-     nkClosure:
+     nkClosure, nkTypeSection:
     # don't recurse here:
     # XXX recurse here and setup 'up' pointers
     discard
@@ -537,13 +539,6 @@ proc newAsgnStmt(le, ri: PNode, info: TLineInfo): PNode =
   result.sons[0] = le
   result.sons[1] = ri
 
-proc addVar*(father, v: PNode) = 
-  var vpart = newNodeI(nkIdentDefs, v.info)
-  addSon(vpart, v)
-  addSon(vpart, ast.emptyNode)
-  addSon(vpart, ast.emptyNode)
-  addSon(father, vpart)
-
 proc newClosureCreationVar(o: POuterContext; e: PEnv): PSym =
   result = newSym(skVar, getIdent(envName), o.fn, e.attachedNode.info)
   incl(result.flags, sfShadowed)
@@ -653,7 +648,7 @@ proc outerProcSons(o: POuterContext, n: PNode) =
 proc liftIterSym*(n: PNode): PNode =
   # transforms  (iter)  to  (let env = newClosure[iter](); (iter, env)) 
   let iter = n.sym
-  assert iter.kind == skIterator
+  assert iter.kind == skClosureIterator
 
   result = newNodeIT(nkStmtListExpr, n.info, n.typ)
   
@@ -679,7 +674,7 @@ proc transformOuterProc(o: POuterContext, n: PNode): PNode =
 
     var closure = PEnv(idTableGet(o.lambdasToEnv, local))
 
-    if local.kind == skIterator and local.typ.callConv == ccClosure:
+    if local.kind == skClosureIterator:
       # consider: [i1, i2, i1]  Since we merged the iterator's closure
       # with the captured owning variables, we need to generate the
       # closure generation code again:
@@ -843,10 +838,10 @@ proc liftForLoop*(body: PNode): PNode =
   
   # static binding?
   var env: PSym
-  if call[0].kind == nkSym and call[0].sym.kind == skIterator:
+  if call[0].kind == nkSym and call[0].sym.kind == skClosureIterator:
     # createClosure()
     let iter = call[0].sym
-    assert iter.kind == skIterator
+    assert iter.kind == skClosureIterator
     env = copySym(getHiddenParam(iter))
 
     var v = newNodeI(nkVarSection, body.info)
diff --git a/compiler/lexer.nim b/compiler/lexer.nim
index 0e7df13cd..217e33675 100644
--- a/compiler/lexer.nim
+++ b/compiler/lexer.nim
@@ -101,6 +101,7 @@ type
     base10,                   # base10 is listed as the first element,
                               # so that it is the correct default value
     base2, base8, base16
+
   TToken* = object            # a Nimrod token
     tokType*: TTokType        # the type of the token
     indent*: int              # the indentation; != -1 if the token has been
@@ -110,6 +111,8 @@ type
     fNumber*: BiggestFloat    # the parsed floating point literal
     base*: TNumericalBase     # the numerical base; only valid for int
                               # or float literals
+    strongSpaceA*: int8       # leading spaces of an operator
+    strongSpaceB*: int8       # trailing spaces of an operator
     literal*: string          # the parsed (string) literal; and
                               # documentation comments are here too
     line*, col*: int
@@ -119,7 +122,9 @@ type
     indentAhead*: int         # if > 0 an indendation has already been read
                               # this is needed because scanning comments
                               # needs so much look-ahead
-  
+    currLineIndent*: int
+    strongSpaces*: bool
+
 
 var gLinesCompiled*: int  # all lines that have been compiled
 
@@ -173,6 +178,7 @@ proc prettyTok*(tok: TToken): string =
   else: result = tokToStr(tok)
   
 proc printTok*(tok: TToken) = 
+  write(stdout, tok.line, ":", tok.col, "\t")
   write(stdout, TokTypeToStr[tok.tokType])
   write(stdout, " ")
   writeln(stdout, tokToStr(tok))
@@ -183,6 +189,7 @@ proc initToken*(L: var TToken) =
   L.tokType = tkInvalid
   L.iNumber = 0
   L.indent = 0
+  L.strongSpaceA = 0
   L.literal = ""
   L.fNumber = 0.0
   L.base = base10
@@ -192,6 +199,7 @@ proc fillToken(L: var TToken) =
   L.tokType = tkInvalid
   L.iNumber = 0
   L.indent = 0
+  L.strongSpaceA = 0
   setLen(L.literal, 0)
   L.fNumber = 0.0
   L.base = base10
@@ -201,6 +209,7 @@ proc openLexer(lex: var TLexer, fileIdx: int32, inputstream: PLLStream) =
   openBaseLexer(lex, inputstream)
   lex.fileIdx = fileidx
   lex.indentAhead = - 1
+  lex.currLineIndent = 0
   inc(lex.lineNumber, inputstream.lineOffset) 
 
 proc closeLexer(lex: var TLexer) = 
@@ -634,6 +643,14 @@ proc getOperator(L: var TLexer, tok: var TToken) =
     h = h !& ord(c)
     inc(pos)
   endOperator(L, tok, pos, h)
+  # advance pos but don't store it in L.bufpos so the next token (which might
+  # be an operator too) gets the preceeding spaces:
+  tok.strongSpaceB = 0
+  while buf[pos] == ' ':
+    inc pos
+    inc tok.strongSpaceB
+  if buf[pos] in {CR, LF, nimlexbase.EndOfFile}:
+    tok.strongSpaceB = -1
 
 proc scanComment(L: var TLexer, tok: var TToken) = 
   var pos = L.bufpos
@@ -677,10 +694,12 @@ proc scanComment(L: var TLexer, tok: var TToken) =
 proc skip(L: var TLexer, tok: var TToken) =
   var pos = L.bufpos
   var buf = L.buf
+  tok.strongSpaceA = 0
   while true:
     case buf[pos]
     of ' ':
       inc(pos)
+      inc(tok.strongSpaceA)
     of Tabulator:
       lexMessagePos(L, errTabulatorsAreNotAllowed, pos)
       inc(pos)
@@ -691,8 +710,10 @@ proc skip(L: var TLexer, tok: var TToken) =
       while buf[pos] == ' ':
         inc(pos)
         inc(indent)
+      tok.strongSpaceA = 0
       if buf[pos] > ' ':
         tok.indent = indent
+        L.currLineIndent = indent
         break
     else:
       break                   # EndOfFile also leaves the loop
@@ -702,6 +723,7 @@ proc rawGetTok(L: var TLexer, tok: var TToken) =
   fillToken(tok)
   if L.indentAhead >= 0:
     tok.indent = L.indentAhead
+    L.currLineIndent = L.indentAhead
     L.indentAhead = -1
   else:
     tok.indent = -1
@@ -811,5 +833,5 @@ proc rawGetTok(L: var TLexer, tok: var TToken) =
         tok.tokType = tkInvalid
         lexMessage(L, errInvalidToken, c & " (\\" & $(ord(c)) & ')')
         inc(L.bufpos)
-  
+
 dummyIdent = getIdent("")
diff --git a/compiler/lookups.nim b/compiler/lookups.nim
index c31eb3121..60125177c 100644
--- a/compiler/lookups.nim
+++ b/compiler/lookups.nim
@@ -32,6 +32,7 @@ proc considerAcc*(n: PNode): PIdent =
         of nkSym: id.add(x.sym.name.s)
         else: globalError(n.info, errIdentifierExpected, renderTree(n))
       result = getIdent(id)
+  of nkOpenSymChoice, nkClosedSymChoice: result = n.sons[0].sym.name
   else:
     globalError(n.info, errIdentifierExpected, renderTree(n))
  
@@ -91,7 +92,7 @@ proc errorSym*(c: PContext, n: PNode): PSym =
   result.typ = errorType(c)
   incl(result.flags, sfDiscardable)
   # pretend it's imported from some unknown module to prevent cascading errors:
-  if gCmd != cmdInteractive:
+  if gCmd != cmdInteractive and c.inCompilesContext == 0:
     c.importTable.addSym(result)
 
 type 
@@ -108,7 +109,7 @@ type
 
 proc getSymRepr*(s: PSym): string = 
   case s.kind
-  of skProc, skMethod, skConverter, skIterator: result = getProcHeader(s)
+  of skProc, skMethod, skConverter, skIterators: result = getProcHeader(s)
   else: result = s.name.s
 
 proc ensureNoMissingOrUnusedSymbols(scope: PScope) =
@@ -126,7 +127,10 @@ proc ensureNoMissingOrUnusedSymbols(scope: PScope) =
     elif {sfUsed, sfExported} * s.flags == {} and optHints in s.options: 
       # BUGFIX: check options in s!
       if s.kind notin {skForVar, skParam, skMethod, skUnknown, skGenericParam}:
-        message(s.info, hintXDeclaredButNotUsed, getSymRepr(s))
+        # XXX: implicit type params are currently skTypes
+        # maybe they can be made skGenericParam as well.
+        if s.typ != nil and tfImplicitTypeParam notin s.typ.flags:
+          message(s.info, hintXDeclaredButNotUsed, getSymRepr(s))
     s = nextIter(it, scope.symbols)
   
 proc wrongRedefinition*(info: TLineInfo, s: string) =
diff --git a/compiler/lowerings.nim b/compiler/lowerings.nim
new file mode 100644
index 000000000..2cf641d93
--- /dev/null
+++ b/compiler/lowerings.nim
@@ -0,0 +1,52 @@
+#
+#
+#           The Nimrod Compiler
+#        (c) Copyright 2014 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## This module implements common simple lowerings.
+
+const
+  genPrefix* = ":tmp"         # prefix for generated names
+
+import ast, types, idents, magicsys
+
+proc newTupleAccess*(tup: PNode, i: int): PNode =
+  result = newNodeIT(nkBracketExpr, tup.info, tup.typ.skipTypes(
+                     abstractInst).sons[i])
+  addSon(result, copyTree(tup))
+  var lit = newNodeIT(nkIntLit, tup.info, getSysType(tyInt))
+  lit.intVal = i
+  addSon(result, lit)
+
+proc addVar*(father, v: PNode) = 
+  var vpart = newNodeI(nkIdentDefs, v.info, 3)
+  vpart.sons[0] = v
+  vpart.sons[1] = ast.emptyNode
+  vpart.sons[2] = ast.emptyNode
+  addSon(father, vpart)
+
+proc newAsgnStmt(le, ri: PNode): PNode =
+  result = newNodeI(nkAsgn, le.info, 2)
+  result.sons[0] = le
+  result.sons[1] = ri
+
+proc lowerTupleUnpacking*(n: PNode; owner: PSym): PNode =
+  assert n.kind == nkVarTuple
+  let value = n.lastSon
+  result = newNodeI(nkStmtList, n.info)
+
+  var temp = newSym(skTemp, getIdent(genPrefix), owner, value.info)
+  temp.typ = skipTypes(value.typ, abstractInst)
+  incl(temp.flags, sfFromGeneric)
+
+  var v = newNodeI(nkVarSection, value.info)
+  v.addVar(newSymNode(temp))
+  result.add(v)
+  
+  result.add newAsgnStmt(newSymNode(temp), value)
+  for i in 0 .. n.len-3:
+    result.add newAsgnStmt(n.sons[i], newTupleAccess(value, i))
diff --git a/compiler/modules.nim b/compiler/modules.nim
index 6a1491682..fb1940741 100644
--- a/compiler/modules.nim
+++ b/compiler/modules.nim
@@ -1,7 +1,7 @@
 #
 #
 #           The Nimrod Compiler
-#        (c) Copyright 2013 Andreas Rumpf
+#        (c) Copyright 2014 Andreas Rumpf
 #
 #    See the file "copying.txt", included in this
 #    distribution, for details about the copyright.
@@ -20,7 +20,7 @@ type
   TModuleInMemory* = object
     compiledAt*: float
     crc*: TCrc32
-    deps*: seq[int32] ## XXX: slurped files are not currently tracked
+    deps*: seq[int32] ## XXX: slurped files are currently not tracked
     needsRecompile*: TNeedRecompile
     crcStatus*: TCrcStatus
 
@@ -83,7 +83,7 @@ proc resetAllModules* =
   for i in 0..gCompiledModules.high:
     if gCompiledModules[i] != nil:
       resetModule(i.int32)
-
+  resetPackageCache()
   # for m in cgenModules(): echo "CGEN MODULE FOUND"
 
 proc checkDepMem(fileIdx: int32): TNeedRecompile =
@@ -120,8 +120,9 @@ proc newModule(fileIdx: int32): PSym =
   if not isNimrodIdentifier(result.name.s):
     rawMessage(errInvalidModuleName, result.name.s)
   
-  result.owner = result       # a module belongs to itself
   result.info = newLineInfo(fileIdx, 1, 1)
+  result.owner = newSym(skPackage, getIdent(getPackageName(filename)), nil,
+                        result.info)
   result.position = fileIdx
   
   growCache gMemCacheData, fileIdx
diff --git a/compiler/msgs.nim b/compiler/msgs.nim
index 61336aa87..a63fbca7f 100644
--- a/compiler/msgs.nim
+++ b/compiler/msgs.nim
@@ -67,7 +67,7 @@ type
     errAmbiguousCallXYZ, errWrongNumberOfArguments, 
     errXCannotBePassedToProcVar, 
     errXCannotBeInParamDecl, errPragmaOnlyInHeaderOfProc, errImplOfXNotAllowed, 
-    errImplOfXexpected, errNoSymbolToBorrowFromFound, errDiscardValue, 
+    errImplOfXexpected, errNoSymbolToBorrowFromFound, errDiscardValueX, 
     errInvalidDiscard, errIllegalConvFromXtoY, errCannotBindXTwice, 
     errInvalidOrderInArrayConstructor,
     errInvalidOrderInEnumX, errEnumXHasHoles, errExceptExpected, errInvalidTry, 
@@ -88,14 +88,16 @@ type
     errTemplateInstantiationTooNested, errInstantiationFrom, 
     errInvalidIndexValueForTuple, errCommandExpectsFilename,
     errMainModuleMustBeSpecified,
-    errXExpected, 
+    errXExpected,
+    errTIsNotAConcreteType,
     errInvalidSectionStart, errGridTableNotImplemented, errGeneralParseError, 
     errNewSectionExpected, errWhitespaceExpected, errXisNoValidIndexFile, 
     errCannotRenderX, errVarVarTypeNotAllowed, errInstantiateXExplicitely,
     errOnlyACallOpCanBeDelegator, errUsingNoSymbol,
+    errMacroBodyDependsOnGenericTypes,
     errDestructorNotGenericEnough,
-    
-    errXExpectsTwoArguments, 
+    errInlineIteratorsAsProcParams,
+    errXExpectsTwoArguments,
     errXExpectsObjectTypes, errXcanNeverBeOfThisSubtype, errTooManyIterations, 
     errCannotInterpretNodeX, errFieldXNotFound, errInvalidConversionFromTypeX, 
     errAssertionFailed, errCannotGenerateCodeForX, errXRequiresOneArgument, 
@@ -103,6 +105,10 @@ type
     errXhasSideEffects, errIteratorExpected, errLetNeedsInit,
     errThreadvarCannotInit, errWrongSymbolX, errIllegalCaptureX,
     errXCannotBeClosure, errXMustBeCompileTime,
+    errCannotInferTypeOfTheLiteral,
+    errCannotInferReturnType,
+    errGenericLambdaNotAllowed,
+    errCompilerDoesntSupportTarget,
     errUser,
     warnCannotOpenFile, 
     warnOctalEscape, warnXIsNeverRead, warnXmightNotBeenInit, 
@@ -196,7 +202,7 @@ const
     errXExpectsArrayType: "\'$1\' expects an array type", 
     errIteratorCannotBeInstantiated: "'$1' cannot be instantiated because its body has not been compiled yet", 
     errExprXAmbiguous: "expression '$1' ambiguous in this context", 
-    errConstantDivisionByZero: "constant division by zero", 
+    errConstantDivisionByZero: "division by zero", 
     errOrdinalTypeExpected: "ordinal type expected", 
     errOrdinalOrFloatTypeExpected: "ordinal or float type expected", 
     errOverOrUnderflow: "over- or underflow", 
@@ -263,7 +269,7 @@ const
     errImplOfXNotAllowed: "implementation of \'$1\' is not allowed", 
     errImplOfXexpected: "implementation of \'$1\' expected", 
     errNoSymbolToBorrowFromFound: "no symbol to borrow from found", 
-    errDiscardValue: "value returned by statement has to be discarded", 
+    errDiscardValueX: "value of type '$1' has to be discarded", 
     errInvalidDiscard: "statement returns no value that can be discarded", 
     errIllegalConvFromXtoY: "conversion from $1 to $2 is invalid",
     errCannotBindXTwice: "cannot bind parameter \'$1\' twice", 
@@ -312,6 +318,7 @@ const
     errCommandExpectsFilename: "command expects a filename argument",
     errMainModuleMustBeSpecified: "please, specify a main module in the project configuration file",
     errXExpected: "\'$1\' expected", 
+    errTIsNotAConcreteType: "\'$1\' is not a concrete type.",
     errInvalidSectionStart: "invalid section start",
     errGridTableNotImplemented: "grid table is not implemented", 
     errGeneralParseError: "general parse error",
@@ -323,8 +330,12 @@ const
     errInstantiateXExplicitely: "instantiate '$1' explicitely",
     errOnlyACallOpCanBeDelegator: "only a call operator can be a delegator",
     errUsingNoSymbol: "'$1' is not a variable, constant or a proc name",
+    errMacroBodyDependsOnGenericTypes: "the macro body cannot be compiled, " &
+                                       "because the parameter '$1' has a generic type",
     errDestructorNotGenericEnough: "Destructor signarue is too specific. " &
                                    "A destructor must be associated will all instantiations of a generic type",
+    errInlineIteratorsAsProcParams: "inline iterators can be used as parameters only for " &
+                                    "templates, macros and other inline iterators",
     errXExpectsTwoArguments: "\'$1\' expects two arguments", 
     errXExpectsObjectTypes: "\'$1\' expects object types",
     errXcanNeverBeOfThisSubtype: "\'$1\' can never be of this subtype", 
@@ -346,6 +357,12 @@ const
     errIllegalCaptureX: "illegal capture '$1'",
     errXCannotBeClosure: "'$1' cannot have 'closure' calling convention",
     errXMustBeCompileTime: "'$1' can only be used in compile-time context",
+    errCannotInferTypeOfTheLiteral: "cannot infer the type of the $1",
+    errCannotInferReturnType: "cannot infer the return type of the proc",
+    errGenericLambdaNotAllowed: "A nested proc can have generic parameters only when " &
+                                "it is used as an operand to another routine and the types " &
+                                "of the generic paramers can be infered from the expected signature.",
+    errCompilerDoesntSupportTarget: "The current compiler \'$1\' doesn't support the requested compilation target",
     errUser: "$1", 
     warnCannotOpenFile: "cannot open \'$1\' [CannotOpenFile]",
     warnOctalEscape: "octal escape sequences do not exist; leading zero is ignored [OctalEscape]", 
@@ -710,19 +727,19 @@ proc handleError(msg: TMsgKind, eh: TErrorHandling, s: string) =
       writeStackTrace()
     quit 1
 
-  if msg >= fatalMin and msg <= fatalMax: 
+  if msg >= fatalMin and msg <= fatalMax:
     quit()
-  if msg >= errMin and msg <= errMax: 
+  if msg >= errMin and msg <= errMax:
     inc(gErrorCounter)
     options.gExitcode = 1'i8
-    if gErrorCounter >= gErrorMax: 
+    if gErrorCounter >= gErrorMax:
       quit()
     elif eh == doAbort and gCmd != cmdIdeTools:
       quit()
     elif eh == doRaise:
       raiseRecoverableError(s)
 
-proc `==`*(a, b: TLineInfo): bool = 
+proc `==`*(a, b: TLineInfo): bool =
   result = a.line == b.line and a.fileIndex == b.fileIndex
 
 proc writeContext(lastinfo: TLineInfo) = 
diff --git a/compiler/nimeval.nim b/compiler/nimeval.nim
index a239d4ef2..0ee108d48 100644
--- a/compiler/nimeval.nim
+++ b/compiler/nimeval.nim
@@ -17,11 +17,11 @@ proc execute*(program: string) =
   passes.gIncludeFile = includeModule
   passes.gImportModule = importModule
   initDefines()
-  LoadConfigs(DefaultConfig)
+  loadConfigs(DefaultConfig)
 
   initDefines()
-  DefineSymbol("nimrodvm")
-  when hasFFI: DefineSymbol("nimffi")
+  defineSymbol("nimrodvm")
+  when hasFFI: defineSymbol("nimffi")
   registerPass(verbosePass)
   registerPass(semPass)
   registerPass(vmPass)
@@ -30,4 +30,4 @@ proc execute*(program: string) =
   compileSystemModule()
   var m = makeStdinModule()
   incl(m.flags, sfMainModule)
-  processModule(m, LLStreamOpen(program), nil)
+  processModule(m, llStreamOpen(program), nil)
diff --git a/compiler/nimrod.nimrod.cfg b/compiler/nimrod.nimrod.cfg
index 657c47b28..cc27d9f36 100644
--- a/compiler/nimrod.nimrod.cfg
+++ b/compiler/nimrod.nimrod.cfg
@@ -17,4 +17,6 @@ import:testability
   cincludes: "$lib/wrappers/libffi/common"
 @end
 
+define:useStdoutAsStdmsg
+
 cs:partial
diff --git a/compiler/options.nim b/compiler/options.nim
index 4f642e626..102ebc386 100644
--- a/compiler/options.nim
+++ b/compiler/options.nim
@@ -209,21 +209,42 @@ proc getGeneratedPath: string =
   result = if nimcacheDir.len > 0: nimcacheDir else: gProjectPath.shortenDir /
                                                          genSubDir
 
+template newPackageCache(): expr =
+  newStringTable(when FileSystemCaseSensitive:
+                   modeCaseInsensitive
+                 else:
+                   modeCaseSensitive)
+
+var packageCache = newPackageCache()
+
+proc resetPackageCache*() = packageCache = newPackageCache()
+
+iterator myParentDirs(p: string): string =
+  # XXX os's parentDirs is stupid (multiple yields) and triggers an old bug...
+  var current = p
+  while true:
+    current = current.parentDir
+    if current.len == 0: break
+    yield current
+
 proc getPackageName*(path: string): string =
-  var q = 1
-  var b = 0
-  if path[len(path)-1] in {DirSep, AltSep}: q = 2
-  for i in countdown(len(path)-q, 0):
-    if path[i] in {DirSep, AltSep}:
-      if b == 0: b = i
-      else:
-        let x = path.substr(i+1, b-1)
-        case x.normalize
-        of "lib", "src", "source", "package", "pckg", "library", "private":
-          b = i
-        else:
-          return x.replace('.', '_')
-  result = ""
+  var parents = 0
+  block packageSearch:
+    for d in myParentDirs(path):
+      if packageCache.hasKey(d):
+        #echo "from cache ", d, " |", packageCache[d], "|", path.splitFile.name
+        return packageCache[d]
+      inc parents
+      for file in walkFiles(d / "*.babel"):
+        result = file.splitFile.name
+        break packageSearch
+  # we also store if we didn't find anything:
+  if result.isNil: result = ""
+  for d in myParentDirs(path):
+    #echo "set cache ", d, " |", result, "|", parents
+    packageCache[d] = result
+    dec parents
+    if parents <= 0: break
 
 proc withPackageName*(path: string): string =
   let x = path.getPackageName
diff --git a/compiler/parser.nim b/compiler/parser.nim
index ff3324b47..07f5c9de9 100644
--- a/compiler/parser.nim
+++ b/compiler/parser.nim
@@ -38,7 +38,6 @@ type
     inSemiStmtList: int
 
 proc parseAll*(p: var TParser): PNode
-proc openParser*(p: var TParser, filename: string, inputstream: PLLStream)
 proc closeParser*(p: var TParser)
 proc parseTopLevelStmt*(p: var TParser): PNode
   # implements an iterator. Returns the next top-level statement or
@@ -50,7 +49,6 @@ proc parseString*(s: string, filename: string = "", line: int = 0): PNode
   # correct error messages referring to the original source.
   
 # helpers for the other parsers
-proc getPrecedence*(tok: TToken): int
 proc isOperator*(tok: TToken): bool
 proc getTok*(p: var TParser)
 proc parMessage*(p: TParser, msg: TMsgKind, arg: string = "")
@@ -69,7 +67,7 @@ proc optPar*(p: var TParser)
 proc optInd*(p: var TParser, n: PNode)
 proc indAndComment*(p: var TParser, n: PNode)
 proc setBaseFlags*(n: PNode, base: TNumericalBase)
-proc parseSymbol*(p: var TParser): PNode
+proc parseSymbol*(p: var TParser, allowNil = false): PNode
 proc parseTry(p: var TParser): PNode
 proc parseCase(p: var TParser): PNode
 # implementation
@@ -77,14 +75,17 @@ proc parseCase(p: var TParser): PNode
 proc getTok(p: var TParser) = 
   rawGetTok(p.lex, p.tok)
 
-proc openParser*(p: var TParser, fileIdx: int32, inputStream: PLLStream) =
+proc openParser*(p: var TParser, fileIdx: int32, inputStream: PLLStream,
+                 strongSpaces=false) =
   initToken(p.tok)
   openLexer(p.lex, fileIdx, inputStream)
   getTok(p)                   # read the first token
   p.firstTok = true
+  p.strongSpaces = strongSpaces
 
-proc openParser*(p: var TParser, filename: string, inputStream: PLLStream) =
-  openParser(p, filename.fileInfoIdx, inputstream)
+proc openParser*(p: var TParser, filename: string, inputStream: PLLStream,
+                 strongSpaces=false) =
+  openParser(p, filename.fileInfoIdx, inputstream, strongSpaces)
 
 proc closeParser(p: var TParser) = 
   closeLexer(p.lex)
@@ -193,34 +194,52 @@ proc isSigilLike(tok: TToken): bool {.inline.} =
 proc isLeftAssociative(tok: TToken): bool {.inline.} =
   result = tok.tokType != tkOpr or relevantOprChar(tok.ident) != '^'
 
-proc getPrecedence(tok: TToken): int = 
+proc getPrecedence(tok: TToken, strongSpaces: bool): int =
+  template considerStrongSpaces(x): expr =
+    x + (if strongSpaces: 100 - tok.strongSpaceA.int*10 else: 0)
+
   case tok.tokType
   of tkOpr:
     let L = tok.ident.s.len
     let relevantChar = relevantOprChar(tok.ident)
     
-    template considerAsgn(value: expr) = 
-      result = if tok.ident.s[L-1] == '=': 1 else: value     
+    template considerAsgn(value: expr) =
+      result = if tok.ident.s[L-1] == '=': 1 else: considerStrongSpaces(value)
     
     case relevantChar
     of '$', '^': considerAsgn(10)
     of '*', '%', '/', '\\': considerAsgn(9)
-    of '~': result = 8
+    of '~': result = considerStrongSpaces(8)
     of '+', '-', '|': considerAsgn(8)
     of '&': considerAsgn(7)
-    of '=', '<', '>', '!': result = 5
+    of '=', '<', '>', '!': result = considerStrongSpaces(5)
     of '.': considerAsgn(6)
-    of '?': result = 2
+    of '?': result = considerStrongSpaces(2)
     else: considerAsgn(2)
   of tkDiv, tkMod, tkShl, tkShr: result = 9
   of tkIn, tkNotin, tkIs, tkIsnot, tkNot, tkOf, tkAs: result = 5
-  of tkDotDot: result = 6
+  of tkDotDot: result = considerStrongSpaces(6)
   of tkAnd: result = 4
   of tkOr, tkXor: result = 3
-  else: result = - 10
-  
-proc isOperator(tok: TToken): bool = 
-  result = getPrecedence(tok) >= 0
+  else: result = -10
+
+proc isOperator(tok: TToken): bool =
+  tok.tokType in {tkOpr, tkDiv, tkMod, tkShl, tkShr, tkIn, tkNotin, tkIs,
+                  tkIsnot, tkNot, tkOf, tkAs, tkDotDot, tkAnd, tkOr, tkXor}
+
+proc isUnary(p: TParser): bool =
+  p.strongSpaces and p.tok.tokType in {tkOpr, tkDotDot} and
+    p.tok.strongSpaceB == 0 and
+    p.tok.strongSpaceA > 0
+
+proc checkBinary(p: TParser) {.inline.} =
+  # we don't check '..' here as that's too annoying
+  if p.strongSpaces and p.tok.tokType == tkOpr:
+    if p.tok.strongSpaceB > 0 and p.tok.strongSpaceA != p.tok.strongSpaceB:
+      parMessage(p, errGenerated, "number of spaces around '$#' not consistent"%
+        prettyTok(p.tok))
+    elif p.tok.strongSpaceA notin {0,1,2,4,8}:
+      parMessage(p, errGenerated, "number of spaces must be 0,1,2,4 or 8")
 
 #| module = stmt ^* (';' / IND{=})
 #|
@@ -254,7 +273,7 @@ proc colcom(p: var TParser, n: PNode) =
   eat(p, tkColon)
   skipComment(p, n)
 
-proc parseSymbol(p: var TParser): PNode =
+proc parseSymbol(p: var TParser, allowNil = false): PNode =
   #| symbol = '`' (KEYW|IDENT|operator|'(' ')'|'[' ']'|'{' '}'|'='|literal)+ '`'
   #|        | IDENT
   case p.tok.tokType
@@ -281,7 +300,7 @@ proc parseSymbol(p: var TParser): PNode =
         add(result, newIdentNodeP(getIdent"{}", p))
         getTok(p)
         eat(p, tkCurlyRi)
-      of tokKeywordLow..tokKeywordHigh, tkSymbol, tkOpr, tkDotDot:
+      of tokKeywordLow..tokKeywordHigh, tkSymbol, tkOpr, tkDot, tkDotDot:
         add(result, newIdentNodeP(p.tok.ident, p))
         getTok(p)
       of tkIntLit..tkCharLit:
@@ -293,9 +312,13 @@ proc parseSymbol(p: var TParser): PNode =
         break
     eat(p, tkAccent)
   else:
-    parMessage(p, errIdentifierExpected, p.tok)
-    getTok(p) # BUGFIX: We must consume a token here to prevent endless loops!
-    result = ast.emptyNode
+    if allowNil and p.tok.tokType == tkNil:
+      result = newNodeP(nkNilLit, p)
+      getTok(p)
+    else:
+      parMessage(p, errIdentifierExpected, p.tok)
+      getTok(p) # BUGFIX: We must consume a token here to prevent endless loops!
+      result = ast.emptyNode
 
 proc indexExpr(p: var TParser): PNode = 
   #| indexExpr = expr
@@ -502,6 +525,8 @@ proc parsePar(p: var TParser): PNode =
       asgn.sons[0] = a
       asgn.sons[1] = b
       result.add(asgn)
+      if p.tok.tokType == tkSemiColon:
+        semiStmtList(p, result)
     elif p.tok.tokType == tkSemiColon:
       # stmt context:
       result.add(a)
@@ -639,7 +664,7 @@ proc namedParams(p: var TParser, callee: PNode,
   exprColonEqExprListAux(p, endTok, result)
 
 proc parseMacroColon(p: var TParser, x: PNode): PNode
-proc primarySuffix(p: var TParser, r: PNode): PNode =
+proc primarySuffix(p: var TParser, r: PNode, baseIndent: int): PNode =
   #| primarySuffix = '(' (exprColonEqExpr comma?)* ')' doBlocks?
   #|               | doBlocks
   #|               | '.' optInd ('type' | 'addr' | symbol) generalizedLit?
@@ -647,9 +672,11 @@ proc primarySuffix(p: var TParser, r: PNode): PNode =
   #|               | '{' optInd indexExprList optPar '}'
   #|               | &( '`'|IDENT|literal|'cast') expr # command syntax
   result = r
-  while p.tok.indent < 0:
+  while p.tok.indent < 0 or
+       (p.tok.tokType == tkDot and p.tok.indent >= baseIndent):
     case p.tok.tokType
     of tkParLe:
+      if p.strongSpaces and p.tok.strongSpaceA > 0: break
       result = namedParams(p, result, nkCall, tkParRi)
       if result.len > 1 and result.sons[1].kind == nkExprColonExpr:
         result.kind = nkObjConstr
@@ -664,8 +691,10 @@ proc primarySuffix(p: var TParser, r: PNode): PNode =
       result = dotExpr(p, result)
       result = parseGStrLit(p, result)
     of tkBracketLe:
+      if p.strongSpaces and p.tok.strongSpaceA > 0: break
       result = namedParams(p, result, nkBracketExpr, tkBracketRi)
     of tkCurlyLe:
+      if p.strongSpaces and p.tok.strongSpaceA > 0: break
       result = namedParams(p, result, nkCurlyExpr, tkCurlyRi)
     of tkSymbol, tkAccent, tkIntLit..tkCharLit, tkNil, tkCast:
       if p.inPragma == 0:
@@ -691,14 +720,17 @@ proc primarySuffix(p: var TParser, r: PNode): PNode =
       break
     
 proc primary(p: var TParser, mode: TPrimaryMode): PNode
+proc simpleExprAux(p: var TParser, limit: int, mode: TPrimaryMode): PNode
 
-proc simpleExprAux(p: var TParser, limit: int, mode: TPrimaryMode): PNode =
-  result = primary(p, mode)
+proc parseOperators(p: var TParser, headNode: PNode,
+                    limit: int, mode: TPrimaryMode): PNode =
+  result = headNode
   # expand while operators have priorities higher than 'limit'
-  var opPrec = getPrecedence(p.tok)
+  var opPrec = getPrecedence(p.tok, p.strongSpaces)
   let modeB = if mode == pmTypeDef: pmTypeDesc else: mode
   # the operator itself must not start on a new line:
-  while opPrec >= limit and p.tok.indent < 0:
+  while opPrec >= limit and p.tok.indent < 0 and not isUnary(p):
+    checkBinary(p)
     var leftAssoc = ord(isLeftAssociative(p.tok))
     var a = newNodeP(nkInfix, p)
     var opNode = newIdentNodeP(p.tok.ident, p) # skip operator:
@@ -710,7 +742,11 @@ proc simpleExprAux(p: var TParser, limit: int, mode: TPrimaryMode): PNode =
     addSon(a, result)
     addSon(a, b)
     result = a
-    opPrec = getPrecedence(p.tok)
+    opPrec = getPrecedence(p.tok, p.strongSpaces)
+
+proc simpleExprAux(p: var TParser, limit: int, mode: TPrimaryMode): PNode =
+  result = primary(p, mode)
+  result = parseOperators(p, result, limit, mode)
   
 proc simpleExpr(p: var TParser, mode = pmNormal): PNode =
   result = simpleExprAux(p, -1, mode)
@@ -934,14 +970,30 @@ proc isExprStart(p: TParser): bool =
      tkTuple, tkObject, tkType, tkWhen, tkCase, tkShared:
     result = true
   else: result = false
-  
-proc parseTypeDescKAux(p: var TParser, kind: TNodeKind, 
-                       mode: TPrimaryMode): PNode = 
+
+proc parseSymbolList(p: var TParser, result: PNode, allowNil = false) =
+  while true:
+    var s = parseSymbol(p, allowNil)
+    if s.kind == nkEmpty: break
+    addSon(result, s)
+    if p.tok.tokType != tkComma: break
+    getTok(p)
+    optInd(p, s)
+
+proc parseTypeDescKAux(p: var TParser, kind: TNodeKind,
+                       mode: TPrimaryMode): PNode =
   result = newNodeP(kind, p)
   getTok(p)
   optInd(p, result)
   if not isOperator(p.tok) and isExprStart(p):
     addSon(result, primary(p, mode))
+  if kind == nkDistinctTy and p.tok.tokType in {tkWith, tkWithout}:
+    let nodeKind = if p.tok.tokType == tkWith: nkWith
+                   else: nkWithout
+    getTok(p)
+    let list = newNodeP(nodeKind, p)
+    result.addSon list
+    parseSymbolList(p, list, allowNil = true)
 
 proc parseExpr(p: var TParser): PNode = 
   #| expr = (ifExpr
@@ -958,7 +1010,6 @@ proc parseExpr(p: var TParser): PNode =
 
 proc parseEnum(p: var TParser): PNode
 proc parseObject(p: var TParser): PNode
-proc parseDistinct(p: var TParser): PNode
 proc parseTypeClass(p: var TParser): PNode
 
 proc primary(p: var TParser, mode: TPrimaryMode): PNode = 
@@ -978,8 +1029,9 @@ proc primary(p: var TParser, mode: TPrimaryMode): PNode =
     optInd(p, a)
     if isSigil: 
       #XXX prefix operators
+      let baseInd = p.lex.currLineIndent
       addSon(result, primary(p, pmSkipSuffix))
-      result = primarySuffix(p, result)
+      result = primarySuffix(p, result, baseInd)
     else:
       addSon(result, primary(p, pmNormal))
     return
@@ -1042,9 +1094,10 @@ proc primary(p: var TParser, mode: TPrimaryMode): PNode =
     optInd(p, result)
     addSon(result, primary(p, pmNormal))
   else:
+    let baseInd = p.lex.currLineIndent
     result = identOrLiteral(p, mode)
     if mode != pmSkipSuffix:
-      result = primarySuffix(p, result)
+      result = primarySuffix(p, result, baseInd)
 
 proc parseTypeDesc(p: var TParser): PNode =
   #| typeDesc = simpleExpr
@@ -1478,7 +1531,7 @@ proc parseSection(p: var TParser, kind: TNodeKind,
                   defparser: TDefParser): PNode =
   #| section(p) = COMMENT? p / (IND{>} (p / COMMENT)^+IND{=} DED)
   result = newNodeP(kind, p)
-  getTok(p)
+  if kind != nkTypeSection: getTok(p)
   skipComment(p, result)
   if realInd(p):
     withInd(p):
@@ -1711,13 +1764,6 @@ proc parseTypeClass(p: var TParser): PNode =
   else:
     addSon(result, parseStmt(p))
 
-proc parseDistinct(p: var TParser): PNode = 
-  #| distinct = 'distinct' optInd typeDesc
-  result = newNodeP(nkDistinctTy, p)
-  getTok(p)
-  optInd(p, result)
-  addSon(result, parseTypeDesc(p))
-
 proc parseTypeDef(p: var TParser): PNode = 
   #| typeDef = identWithPragma genericParamList? '=' optInd typeDefAux
   #|             indAndComment?
@@ -1839,7 +1885,16 @@ proc complexOrSimpleStmt(p: var TParser): PNode =
   of tkMacro: result = parseRoutine(p, nkMacroDef)
   of tkTemplate: result = parseRoutine(p, nkTemplateDef)
   of tkConverter: result = parseRoutine(p, nkConverterDef)
-  of tkType: result = parseSection(p, nkTypeSection, parseTypeDef)
+  of tkType:
+    getTok(p)
+    if p.tok.tokType == tkParLe:
+      getTok(p)
+      result = newNodeP(nkTypeOfExpr, p)
+      result.addSon(primary(p, pmTypeDesc))
+      eat(p, tkParRi)
+      result = parseOperators(p, result, -1, pmNormal)
+    else:
+      result = parseSection(p, nkTypeSection, parseTypeDef)
   of tkConst: result = parseSection(p, nkConstSection, parseConstant)
   of tkLet: result = parseSection(p, nkLetSection, parseVariable)
   of tkWhen: result = parseIfOrWhen(p, nkWhenStmt)
@@ -1863,7 +1918,7 @@ proc parseStmt(p: var TParser): PNode =
           if p.tok.indent < 0 or p.tok.indent == p.currInd: discard
           else: break
         else:
-          if p.tok.indent > p.currInd:
+          if p.tok.indent > p.currInd and p.tok.tokType != tkDot:
             parMessage(p, errInvalidIndentation)
           break
         if p.tok.tokType in {tkCurlyRi, tkParRi, tkCurlyDotRi, tkBracketRi}:
@@ -1890,7 +1945,8 @@ proc parseStmt(p: var TParser): PNode =
       else:
         result = newNodeP(nkStmtList, p)
         while true:
-          if p.tok.indent >= 0: parMessage(p, errInvalidIndentation)     
+          if p.tok.indent >= 0:
+            parMessage(p, errInvalidIndentation)
           let a = simpleStmt(p)
           if a.kind == nkEmpty: parMessage(p, errExprExpected, p.tok)
           result.add(a)
@@ -1933,7 +1989,9 @@ proc parseString(s: string, filename: string = "", line: int = 0): PNode =
   stream.lineOffset = line
 
   var parser: TParser
-  openParser(parser, filename, stream)
+  # XXX for now the builtin 'parseStmt/Expr' functions do not know about strong
+  # spaces...
+  openParser(parser, filename, stream, false)
 
   result = parser.parseAll
   closeParser(parser)
diff --git a/compiler/pas2nim/paslex.nim b/compiler/pas2nim/paslex.nim
index 67473e71f..f24b0c420 100644
--- a/compiler/pas2nim/paslex.nim
+++ b/compiler/pas2nim/paslex.nim
@@ -342,7 +342,7 @@ proc getSymbol(L: var TLexer, tok: var TToken) =
       h = h +% ord(c)
       h = h +% h shl 10
       h = h xor (h shr 6)
-    of '_': nil
+    of '_': discard
     else: break
     inc(pos)
   h = h +% h shl 3
diff --git a/compiler/pas2nim/pasparse.nim b/compiler/pas2nim/pasparse.nim
index 928896338..a6f8363f6 100644
--- a/compiler/pas2nim/pasparse.nim
+++ b/compiler/pas2nim/pasparse.nim
@@ -335,7 +335,7 @@ proc exprColonEqExprList(p: var TParser, kind, elemKind: TNodeKind,
 
 proc setBaseFlags(n: PNode, base: TNumericalBase) = 
   case base
-  of base10: nil
+  of base10: discard
   of base2: incl(n.flags, nfBase2)
   of base8: incl(n.flags, nfBase8)
   of base16: incl(n.flags, nfBase16)
@@ -466,7 +466,7 @@ proc lowestExprAux(p: var TParser, v: var PNode, limit: int): TTokKind =
         eat(p, pxCurlyDirRi)
         opNode.ident = getIdent("&")
       else: 
-        nil
+        discard
     of pxMinus: 
       if p.tok.xkind == pxPer: 
         getTok(p)
@@ -477,7 +477,7 @@ proc lowestExprAux(p: var TParser, v: var PNode, limit: int): TTokKind =
     of pxNeq: 
       opNode.ident = getIdent("!=")
     else: 
-      nil
+      discard
     skipCom(p, opNode)        # read sub-expression with higher priority
     nextop = lowestExprAux(p, v2, opPred)
     addSon(node, opNode)
@@ -505,7 +505,7 @@ proc fixExpr(n: PNode): PNode =
             (n.sons[2].kind in {nkCharLit, nkStrLit}): 
           n.sons[0].ident = getIdent("&") # fix operator
   else: 
-    nil
+    discard
   if not (n.kind in {nkEmpty..nkNilLit}): 
     for i in countup(0, sonsLen(n) - 1): result.sons[i] = fixExpr(n.sons[i])
   
@@ -603,7 +603,7 @@ proc parseStmtList(p: var TParser): PNode =
     of pxCurlyDirLe, pxStarDirLe: 
       if not isHandledDirective(p): break 
     else: 
-      nil
+      discard
     addSon(result, parseStmt(p))
   if sonsLen(result) == 1: result = result.sons[0]
   
@@ -732,7 +732,7 @@ proc parseRepeat(p: var TParser): PNode =
   addSon(b, c)
   addSon(a, b)
   if b.sons[0].kind == nkIdent and b.sons[0].ident.id == getIdent("false").id: 
-    nil
+    discard
   else: 
     addSon(s, a)
   addSon(result, s)
@@ -840,7 +840,7 @@ proc parseParam(p: var TParser): PNode =
     getTok(p)
     v = newNodeP(nkVarTy, p)
   else: 
-    nil
+    discard
   while true: 
     case p.tok.xkind
     of pxSymbol: a = createIdentNodeP(p.tok.ident, p)
@@ -1133,7 +1133,7 @@ proc parseRecordPart(p: var TParser): PNode =
 proc exSymbol(n: var PNode) = 
   case n.kind
   of nkPostfix: 
-    nil
+    discard
   of nkPragmaExpr: 
     exSymbol(n.sons[0])
   of nkIdent, nkAccQuoted: 
@@ -1154,7 +1154,7 @@ proc fixRecordDef(n: var PNode) =
     for i in countup(0, sonsLen(n) - 1): fixRecordDef(n.sons[i])
   of nkIdentDefs: 
     for i in countup(0, sonsLen(n) - 3): exSymbol(n.sons[i])
-  of nkNilLit, nkEmpty: nil
+  of nkNilLit, nkEmpty: discard
   else: internalError(n.info, "fixRecordDef(): " & $n.kind)
   
 proc addPragmaToIdent(ident: var PNode, pragma: PNode) = 
@@ -1191,7 +1191,7 @@ proc parseRecordBody(p: var TParser, result, definition: PNode) =
     if definition != nil: addPragmaToIdent(definition.sons[0], parseCommand(p))
     else: internalError(result.info, "anonymous record is not supported")
   else: 
-    nil
+    discard
   opt(p, pxSemicolon)
   skipCom(p, result)
 
@@ -1399,7 +1399,7 @@ proc fixVarSection(p: var TParser, counter: PNode) =
 
 proc exSymbols(n: PNode) = 
   case n.kind
-  of nkEmpty..nkNilLit: nil
+  of nkEmpty..nkNilLit: discard
   of nkProcDef..nkIteratorDef: exSymbol(n.sons[namePos])
   of nkWhenStmt, nkStmtList: 
     for i in countup(0, sonsLen(n) - 1): exSymbols(n.sons[i])
@@ -1410,7 +1410,7 @@ proc exSymbols(n: PNode) =
       exSymbol(n.sons[i].sons[0])
       if n.sons[i].sons[2].kind == nkObjectTy: 
         fixRecordDef(n.sons[i].sons[2])
-  else: nil
+  else: discard
 
 proc parseBegin(p: var TParser, result: PNode) = 
   getTok(p)
diff --git a/compiler/pragmas.nim b/compiler/pragmas.nim
index d9ed50cfe..14d155539 100644
--- a/compiler/pragmas.nim
+++ b/compiler/pragmas.nim
@@ -23,7 +23,7 @@ const
     wMagic, wNosideeffect, wSideeffect, wNoreturn, wDynlib, wHeader, 
     wCompilerproc, wProcVar, wDeprecated, wVarargs, wCompileTime, wMerge, 
     wBorrow, wExtern, wImportCompilerProc, wThread, wImportCpp, wImportObjC,
-    wNoStackFrame, wError, wDiscardable, wNoInit, wDestructor, wCodegenDecl,
+    wAsmNoStackFrame, wError, wDiscardable, wNoInit, wDestructor, wCodegenDecl,
     wGensym, wInject, wRaises, wTags, wOperator, wDelegator}
   converterPragmas* = procPragmas
   methodPragmas* = procPragmas
@@ -47,12 +47,13 @@ const
     wInjectStmt}
   lambdaPragmas* = {FirstCallConv..LastCallConv, wImportc, wExportc, wNodecl, 
     wNosideeffect, wSideeffect, wNoreturn, wDynlib, wHeader, 
-    wDeprecated, wExtern, wThread, wImportCpp, wImportObjC, wNoStackFrame,
+    wDeprecated, wExtern, wThread, wImportCpp, wImportObjC, wAsmNoStackFrame,
     wRaises, wTags}
   typePragmas* = {wImportc, wExportc, wDeprecated, wMagic, wAcyclic, wNodecl, 
-    wPure, wHeader, wCompilerproc, wFinal, wSize, wExtern, wShallow, 
+    wPure, wHeader, wCompilerproc, wFinal, wSize, wExtern, wShallow,
     wImportCpp, wImportObjC, wError, wIncompleteStruct, wByCopy, wByRef,
-    wInheritable, wGensym, wInject, wRequiresInit}
+    wInheritable, wGensym, wInject, wRequiresInit, wUnchecked, wUnion, wPacked,
+    wBorrow}
   fieldPragmas* = {wImportc, wExportc, wDeprecated, wExtern, 
     wImportCpp, wImportObjC, wError}
   varPragmas* = {wImportc, wExportc, wVolatile, wRegister, wThreadVar, wNodecl, 
@@ -97,8 +98,22 @@ proc makeExternImport(s: PSym, extname: string) =
   incl(s.flags, sfImportc)
   excl(s.flags, sfForward)
 
-proc makeExternExport(s: PSym, extname: string) = 
+proc validateExternCName(s: PSym, info: TLineInfo) =
+  ## Validates that the symbol name in s.loc.r is a valid C identifier.
+  ##
+  ## Valid identifiers are those alphanumeric including the underscore not
+  ## starting with a number. If the check fails, a generic error will be
+  ## displayed to the user.
+  let target = ropeToStr(s.loc.r)
+  if target.len < 1 or target[0] notin IdentStartChars or
+      not target.allCharsInSet(IdentChars):
+    localError(info, errGenerated, "invalid exported symbol")
+
+proc makeExternExport(s: PSym, extname: string, info: TLineInfo) =
   setExternName(s, extname)
+  # XXX to fix make it work with nimrtl.
+  #if gCmd in {cmdCompileToC, cmdCompileToCpp, cmdCompileToOC}:
+  #  validateExternCName(s, info)
   incl(s.flags, sfExportc)
 
 proc processImportCompilerProc(s: PSym, extname: string) =
@@ -498,6 +513,13 @@ proc pragmaRaisesOrTags(c: PContext, n: PNode) =
   else:
     invalidPragma(n)
 
+proc typeBorrow(sym: PSym, n: PNode) =
+  if n.kind == nkExprColonExpr:
+    let it = n.sons[1]
+    if it.kind != nkAccQuoted:
+      localError(n.info, "a type can only borrow `.` for now")
+  incl(sym.typ.flags, tfBorrowDot)
+
 proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
                   validPragmas: TSpecialWords): bool =
   var it = n.sons[i]
@@ -515,7 +537,7 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
       if k in validPragmas: 
         case k
         of wExportc: 
-          makeExternExport(sym, getOptionalStr(c, it, "$1"))
+          makeExternExport(sym, getOptionalStr(c, it, "$1"), it.info)
           incl(sym.flags, sfUsed) # avoid wrong hints
         of wImportc: makeExternImport(sym, getOptionalStr(c, it, "$1"))
         of wImportCompilerProc:
@@ -548,9 +570,11 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
         of wNodecl: 
           noVal(it)
           incl(sym.loc.flags, lfNoDecl)
-        of wPure, wNoStackFrame:
+        of wPure, wAsmNoStackFrame:
           noVal(it)
-          if sym != nil: incl(sym.flags, sfPure)
+          if sym != nil:
+            if k == wPure and sym.kind in routineKinds: invalidPragma(it)
+            else: incl(sym.flags, sfPure)
         of wVolatile: 
           noVal(it)
           incl(sym.flags, sfVolatile)
@@ -601,7 +625,7 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
           processDynLib(c, it, sym)
         of wCompilerproc: 
           noVal(it)           # compilerproc may not get a string!
-          makeExternExport(sym, "$1")
+          makeExternExport(sym, "$1", it.info)
           incl(sym.flags, sfCompilerProc)
           incl(sym.flags, sfUsed) # suppress all those stupid warnings
           registerCompilerProc(sym)
@@ -616,9 +640,12 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
           noVal(it)
           if sym.typ == nil: invalidPragma(it)
           else: incl(sym.typ.flags, tfVarargs)
-        of wBorrow: 
-          noVal(it)
-          incl(sym.flags, sfBorrow)
+        of wBorrow:
+          if sym.kind == skType:
+            typeBorrow(sym, it)
+          else:
+            noVal(it)
+            incl(sym.flags, sfBorrow)
         of wFinal: 
           noVal(it)
           if sym.typ == nil: invalidPragma(it)
@@ -640,6 +667,10 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
           incl(sym.flags, sfThread)
           incl(sym.flags, sfProcvar)
           if sym.typ != nil: incl(sym.typ.flags, tfThread)
+        of wPacked:
+          noVal(it)
+          if sym.typ == nil: invalidPragma(it)
+          else: incl(sym.typ.flags, tfPacked)
         of wHint: message(it.info, hintUser, expectStrLit(c, it))
         of wWarning: message(it.info, warnUser, expectStrLit(c, it))
         of wError: 
@@ -699,6 +730,14 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
           noVal(it)
           if sym.typ == nil: invalidPragma(it)
           else: incl(sym.typ.flags, tfIncompleteStruct)
+        of wUnchecked:
+          noVal(it)
+          if sym.typ == nil: invalidPragma(it)
+          else: incl(sym.typ.flags, tfUncheckedArray)
+        of wUnion:
+          noVal(it)
+          if sym.typ == nil: invalidPragma(it)
+          else: incl(sym.typ.flags, tfUnion)
         of wRequiresInit:
           noVal(it)
           if sym.typ == nil: invalidPragma(it)
@@ -732,8 +771,8 @@ proc singlePragma(c: PContext, sym: PSym, n: PNode, i: int,
       else: invalidPragma(it)
   else: processNote(c, it)
 
-proc implictPragmas*(c: PContext, sym: PSym, n: PNode,
-                     validPragmas: TSpecialWords) =
+proc implicitPragmas*(c: PContext, sym: PSym, n: PNode,
+                      validPragmas: TSpecialWords) =
   if sym != nil and sym.kind != skModule:
     var it = POptionEntry(c.optionStack.head)
     while it != nil:
@@ -744,7 +783,7 @@ proc implictPragmas*(c: PContext, sym: PSym, n: PNode,
             internalError(n.info, "implicitPragmas")
       it = it.next.POptionEntry
 
-    if lfExportLib in sym.loc.flags and sfExportc notin sym.flags: 
+    if lfExportLib in sym.loc.flags and sfExportc notin sym.flags:
       localError(n.info, errDynlibRequiresExportc)
     var lib = POptionEntry(c.optionStack.tail).dynlib
     if {lfDynamicLib, lfHeader} * sym.loc.flags == {} and
@@ -753,8 +792,19 @@ proc implictPragmas*(c: PContext, sym: PSym, n: PNode,
       addToLib(lib, sym)
       if sym.loc.r == nil: sym.loc.r = toRope(sym.name.s)
 
+proc hasPragma*(n: PNode, pragma: TSpecialWord): bool =
+  if n == nil or n.sons == nil:
+    return false
+
+  for p in n.sons:
+    var key = if p.kind == nkExprColonExpr: p[0] else: p
+    if key.kind == nkIdent and whichKeyword(key.ident) == pragma:
+      return true
+  
+  return false
+
 proc pragma(c: PContext, sym: PSym, n: PNode, validPragmas: TSpecialWords) =
   if n == nil: return
   for i in countup(0, sonsLen(n) - 1):
     if singlePragma(c, sym, n, i, validPragmas): break
-  implictPragmas(c, sym, n, validPragmas)
+  implicitPragmas(c, sym, n, validPragmas)
diff --git a/compiler/renderer.nim b/compiler/renderer.nim
index 1afb5961e..2d2310914 100644
--- a/compiler/renderer.nim
+++ b/compiler/renderer.nim
@@ -424,8 +424,11 @@ proc lsub(n: PNode): int =
   of nkRefTy: result = (if n.len > 0: lsub(n.sons[0])+1 else: 0) + len("ref")
   of nkPtrTy: result = (if n.len > 0: lsub(n.sons[0])+1 else: 0) + len("ptr")
   of nkVarTy: result = (if n.len > 0: lsub(n.sons[0])+1 else: 0) + len("var")
-  of nkDistinctTy: result = (if n.len > 0: lsub(n.sons[0])+1 else: 0) +
-                                                         len("Distinct")
+  of nkDistinctTy:
+    result = len("distinct") + (if n.len > 0: lsub(n.sons[0])+1 else: 0)
+    if n.len > 1:
+      result += (if n[1].kind == nkWith: len("_with_") else: len("_without_"))
+      result += lcomma(n[1])
   of nkStaticTy: result = (if n.len > 0: lsub(n.sons[0]) else: 0) +
                                                          len("static[]")
   of nkTypeDef: result = lsons(n) + 3
@@ -558,16 +561,19 @@ proc longMode(n: PNode, start: int = 0, theEnd: int = - 1): bool =
         result = true
         break 
 
-proc gstmts(g: var TSrcGen, n: PNode, c: TContext) = 
-  if n.kind == nkEmpty: return 
+proc gstmts(g: var TSrcGen, n: PNode, c: TContext, doIndent=true) =
+  if n.kind == nkEmpty: return
   if n.kind in {nkStmtList, nkStmtListExpr, nkStmtListType}:
-    indentNL(g)
-    for i in countup(0, sonsLen(n) - 1): 
+    if doIndent: indentNL(g)
+    for i in countup(0, sonsLen(n) - 1):
       optNL(g)
-      gsub(g, n.sons[i])
+      if n.sons[i].kind in {nkStmtList, nkStmtListExpr, nkStmtListType}:
+        gstmts(g, n.sons[i], c, doIndent=false)
+      else:
+        gsub(g, n.sons[i])
       gcoms(g)
-    dedent(g)
-  else: 
+    if doIndent: dedent(g)
+  else:
     if rfLongMode in c.flags: indentNL(g)
     gsub(g, n)
     gcoms(g)
@@ -1017,9 +1023,15 @@ proc gsub(g: var TSrcGen, n: PNode, c: TContext) =
     else:
       put(g, tkVar, "var")
   of nkDistinctTy: 
-    if sonsLen(n) > 0:
+    if n.len > 0:
       putWithSpace(g, tkDistinct, "distinct")
       gsub(g, n.sons[0])
+      if n.len > 1:
+        if n[1].kind == nkWith:
+          putWithSpace(g, tkWith, " with")
+        else:
+          putWithSpace(g, tkWithout, " without")
+        gcomma(g, n[1])
     else:
       put(g, tkDistinct, "distinct")
   of nkTypeDef: 
@@ -1268,7 +1280,7 @@ proc gsub(g: var TSrcGen, n: PNode, c: TContext) =
       put(g, tkBracketLe, "[")
       gcomma(g, n)
       put(g, tkBracketRi, "]")
-  of nkMetaNode:
+  of nkMetaNode_Obsolete:
     put(g, tkParLe, "(META|")
     gsub(g, n.sons[0])
     put(g, tkParRi, ")")
diff --git a/compiler/rodread.nim b/compiler/rodread.nim
index b53135a95..036e6cc3c 100644
--- a/compiler/rodread.nim
+++ b/compiler/rodread.nim
@@ -890,7 +890,7 @@ proc loadStub*(s: PSym) =
   
   # deactivate the GC here because we do a deep recursion and generate no
   # garbage when restoring parts of the object graph anyway.
-  # Since we die with internal errors if this fails, so no try-finally is
+  # Since we die with internal errors if this fails, no try-finally is
   # necessary.
   GC_disable()
   rawLoadStub(s)
diff --git a/compiler/sem.nim b/compiler/sem.nim
index 00ac79716..c35cff027 100644
--- a/compiler/sem.nim
+++ b/compiler/sem.nim
@@ -66,6 +66,9 @@ proc fitNode(c: PContext, formal: PType, arg: PNode): PNode =
       result = copyTree(arg)
       result.typ = formal
 
+proc inferWithMetatype(c: PContext, formal: PType,
+                       arg: PNode, coerceDistincts = false): PNode
+
 var commonTypeBegin = PType(kind: tyExpr)
 
 proc commonType*(x, y: PType): PType =
@@ -120,7 +123,8 @@ proc commonType*(x, y: PType): PType =
     if a.kind == tyObject and b.kind == tyObject:
       result = commonSuperclass(a, b)
       # this will trigger an error later:
-      if result.isNil: return x
+      if result.isNil or result == a: return x
+      if result == b: return y
       if k != tyNone:
         let r = result
         result = newType(k, r.owner)
@@ -138,6 +142,10 @@ proc newSymG*(kind: TSymKind, n: PNode, c: PContext): PSym =
     result = n.sym
     internalAssert sfGenSym in result.flags
     internalAssert result.kind == kind
+    # when there is a nested proc inside a template, semtmpl
+    # will assign a wrong owner during the first pass over the
+    # template; we must fix it here: see #909
+    result.owner = getCurrOwner()
   else:
     result = newSym(kind, considerAcc(n), getCurrOwner(), n.info)
 
@@ -193,7 +201,8 @@ proc fixupTypeAfterEval(c: PContext, evaluated, eOrig: PNode): PNode =
       result = semExprWithType(c, evaluated)
     else:
       result = evaluated
-      semmacrosanity.annotateType(result, eOrig.typ)
+      let expectedType = eOrig.typ.skipTypes({tyStatic})
+      semmacrosanity.annotateType(result, expectedType)
   else:
     result = semExprWithType(c, evaluated)
     #result = fitNode(c, e.typ, result) inlined with special case:
@@ -213,14 +222,26 @@ proc tryConstExpr(c: PContext, n: PNode): PNode =
   result = getConstExpr(c.module, e)
   if result != nil: return
 
+  let oldErrorCount = msgs.gErrorCounter
+  let oldErrorMax = msgs.gErrorMax
+  let oldErrorOutputs = errorOutputs
+
+  errorOutputs = {}
+  msgs.gErrorMax = high(int)
+
   try:
     result = evalConstExpr(c.module, e)
     if result == nil or result.kind == nkEmpty:
-      return nil
+      result = nil
+    else:
+      result = fixupTypeAfterEval(c, result, e)
+
+  except ERecoverableError:
+    result = nil
 
-    result = fixupTypeAfterEval(c, result, e)
-  except:
-    return nil
+  msgs.gErrorCounter = oldErrorCount
+  msgs.gErrorMax = oldErrorMax
+  errorOutputs = oldErrorOutputs
 
 proc semConstExpr(c: PContext, n: PNode): PNode =
   var e = semExprWithType(c, n)
@@ -332,6 +353,8 @@ proc myOpen(module: PSym): PPassContext =
   c.semOperand = semOperand
   c.semConstBoolExpr = semConstBoolExpr
   c.semOverloadedCall = semOverloadedCall
+  c.semInferredLambda = semInferredLambda
+  c.semGenerateInstance = generateInstance
   c.semTypeNode = semTypeNode
   pushProcCon(c, module)
   pushOwner(c.module)
diff --git a/compiler/semcall.nim b/compiler/semcall.nim
index 6b19dc359..04d280ce2 100644
--- a/compiler/semcall.nim
+++ b/compiler/semcall.nim
@@ -64,7 +64,7 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode,
             errors[errors.len - 1].add("\n  " & err)
       if z.state == csMatch:
         # little hack so that iterators are preferred over everything else:
-        if sym.kind == skIterator: inc(z.exactMatches, 200)
+        if sym.kind in skIterators: inc(z.exactMatches, 200)
         case best.state
         of csEmpty, csNoMatch: best = z
         of csMatch:
@@ -82,7 +82,7 @@ proc notFoundError*(c: PContext, n: PNode, errors: seq[string]) =
     # fail fast:
     globalError(n.info, errTypeMismatch, "")
   var result = msgKindToString(errTypeMismatch)
-  add(result, describeArgs(c, n, 1 + ord(nfDelegate in n.flags)))
+  add(result, describeArgs(c, n, 1))
   add(result, ')')
   
   var candidates = ""
@@ -114,7 +114,7 @@ proc resolveOverloads(c: PContext, n, orig: PNode,
 
   var errors: seq[string]
   var usedSyms: seq[PNode]
- 
+
   template pickBest(headSymbol: expr) =
     pickBestCandidate(c, headSymbol, n, orig, initialBinding,
                       filter, result, alt, errors)
@@ -138,17 +138,35 @@ proc resolveOverloads(c: PContext, n, orig: PNode,
 
   let overloadsState = result.state
   if overloadsState != csMatch:
-    if nfDelegate in n.flags:
-      internalAssert f.kind == nkIdent
-      let calleeName = newStrNode(nkStrLit, f.ident.s)
-      calleeName.info = n.info
-
-      let callOp = newIdentNode(idDelegator, n.info)
-      n.sons[0..0] = [callOp, calleeName]
-      orig.sons[0..0] = [callOp, calleeName]
-     
-      pickBest(callOp)
+    if nfDotField in n.flags:
+      internalAssert f.kind == nkIdent and n.sonsLen >= 2
+      let calleeName = newStrNode(nkStrLit, f.ident.s).withInfo(n.info)
+
+      # leave the op head symbol empty,
+      # we are going to try multiple variants
+      n.sons[0..1] = [nil, n[1], calleeName]
+      orig.sons[0..1] = [nil, orig[1], calleeName]
+      
+      template tryOp(x) =
+        let op = newIdentNode(getIdent(x), n.info)
+        n.sons[0] = op
+        orig.sons[0] = op
+        pickBest(op)
+
+      if nfExplicitCall in n.flags:
+        tryOp ".()"
+   
+      if result.state in {csEmpty, csNoMatch}:
+        tryOp "."
 
+    elif nfDotSetter in n.flags:
+      internalAssert f.kind == nkIdent and n.sonsLen == 3
+      let calleeName = newStrNode(nkStrLit, f.ident.s[0.. -2]).withInfo(n.info)
+      let callOp = newIdentNode(getIdent".=", n.info)
+      n.sons[0..1] = [callOp, n[1], calleeName]
+      orig.sons[0..1] = [callOp, orig[1], calleeName]
+      pickBest(callOp)
+   
     if overloadsState == csEmpty and result.state == csEmpty:
       localError(n.info, errUndeclaredIdentifier, considerAcc(f).s)
       return
@@ -157,9 +175,15 @@ proc resolveOverloads(c: PContext, n, orig: PNode,
         localError(n.info, errExprXCannotBeCalled,
                    renderTree(n, {renderNoComments}))
       else:
+        if {nfDotField, nfDotSetter} * n.flags != {}:
+          # clean up the inserted ops
+          n.sons.delete(2)
+          n.sons[0] = f
+
         errors = @[]
         pickBest(f)
         notFoundError(c, n, errors)
+
       return
 
   if alt.state == csMatch and cmpCandidates(result, alt) == 0 and
@@ -204,12 +228,25 @@ proc indexTypesMatch(c: PContext, f, a: PType, arg: PNode): PNode =
   if m.genericConverter and result != nil:
     instGenericConvertersArg(c, result, m)
 
-proc convertTo*(c: PContext, f: PType, n: PNode): PNode = 
+proc inferWithMetatype(c: PContext, formal: PType,
+                       arg: PNode, coerceDistincts = false): PNode =
   var m: TCandidate
-  initCandidate(c, m, f)
-  result = paramTypesMatch(m, f, n.typ, n, nil)
+  initCandidate(c, m, formal)
+  m.coerceDistincts = coerceDistincts
+  result = paramTypesMatch(m, formal, arg.typ, arg, nil)
   if m.genericConverter and result != nil:
     instGenericConvertersArg(c, result, m)
+  if result != nil:
+    # This almost exactly replicates the steps taken by the compiler during
+    # param matching. It performs an embarassing ammount of back-and-forth
+    # type jugling, but it's the price to pay for consistency and correctness
+    result.typ = generateTypeInstance(c, m.bindings, arg.info,
+                                      formal.skipTypes({tyCompositeTypeClass}))
+  else:
+    typeMismatch(arg, formal, arg.typ)
+    # error correction:
+    result = copyTree(arg)
+    result.typ = formal
 
 proc semResolvedCall(c: PContext, n: PNode, x: TCandidate): PNode =
   assert x.state == csMatch
@@ -271,8 +308,9 @@ proc explicitGenericInstantiation(c: PContext, n: PNode, s: PSym): PNode =
     result = newNodeI(a.kind, n.info)
     for i in countup(0, len(a)-1): 
       var candidate = a.sons[i].sym
-      if candidate.kind in {skProc, skMethod, skConverter, skIterator}: 
-        # if suffices that the candidate has the proper number of generic 
+      if candidate.kind in {skProc, skMethod, skConverter,
+                            skIterator, skClosureIterator}:
+        # it suffices that the candidate has the proper number of generic 
         # type parameters:
         if safeLen(candidate.ast.sons[genericParamsPos]) == n.len-1:
           result.add(explicitGenericSym(c, n, candidate))
@@ -288,7 +326,7 @@ proc searchForBorrowProc(c: PContext, startScope: PScope, fn: PSym): PSym =
   # for borrowing the sym in the symbol table is returned, else nil.
   # New approach: generate fn(x, y, z) where x, y, z have the proper types
   # and use the overloading resolution mechanism:
-  var call = newNode(nkCall)
+  var call = newNodeI(nkCall, fn.info)
   var hasDistinct = false
   call.add(newIdentNode(fn.name, fn.info))
   for i in 1.. <fn.typ.n.len:
diff --git a/compiler/semdata.nim b/compiler/semdata.nim
index c9d95e1bf..b46d83a92 100644
--- a/compiler/semdata.nim
+++ b/compiler/semdata.nim
@@ -42,7 +42,7 @@ type
 
   TExprFlag* = enum 
     efLValue, efWantIterator, efInTypeof, efWantStmt, efDetermineType,
-    efAllowDestructor, efWantValue
+    efAllowDestructor, efWantValue, efOperand
   TExprFlags* = set[TExprFlag]
 
   PContext* = ref TContext
@@ -81,6 +81,9 @@ type
     semOverloadedCall*: proc (c: PContext, n, nOrig: PNode,
                               filter: TSymKinds): PNode {.nimcall.}
     semTypeNode*: proc(c: PContext, n: PNode, prev: PType): PType {.nimcall.}
+    semInferredLambda*: proc(c: PContext, pt: TIdTable, n: PNode): PNode
+    semGenerateInstance*: proc (c: PContext, fn: PSym, pt: TIdTable,
+                                info: TLineInfo): PSym
     includedFiles*: TIntSet    # used to detect recursive include files
     userPragmas*: TStrTable
     evalContext*: PEvalContext
@@ -211,7 +214,6 @@ proc makeTypeDesc*(c: PContext, typ: PType): PType =
 
 proc makeTypeSymNode*(c: PContext, typ: PType, info: TLineInfo): PNode =
   let typedesc = makeTypeDesc(c, typ)
-  rawAddSon(typedesc, newTypeS(tyNone, c))
   let sym = newSym(skType, idAnon, getCurrOwner(), info).linkTo(typedesc)
   return newSymNode(sym, info)
 
@@ -234,17 +236,41 @@ proc makeAndType*(c: PContext, t1, t2: PType): PType =
   result.sons = @[t1, t2]
   propagateToOwner(result, t1)
   propagateToOwner(result, t2)
+  result.flags.incl((t1.flags + t2.flags) * {tfHasStatic})
 
 proc makeOrType*(c: PContext, t1, t2: PType): PType =
   result = newTypeS(tyOr, c)
   result.sons = @[t1, t2]
   propagateToOwner(result, t1)
   propagateToOwner(result, t2)
+  result.flags.incl((t1.flags + t2.flags) * {tfHasStatic})
 
 proc makeNotType*(c: PContext, t1: PType): PType =
   result = newTypeS(tyNot, c)
   result.sons = @[t1]
   propagateToOwner(result, t1)
+  result.flags.incl(t1.flags * {tfHasStatic})
+
+proc nMinusOne*(n: PNode): PNode =
+  result = newNode(nkCall, n.info, @[
+    newSymNode(getSysMagic("<", mUnaryLt)),
+    n])
+
+# Remember to fix the procs below this one when you make changes!
+proc makeRangeWithStaticExpr*(c: PContext, n: PNode): PType =
+  let intType = getSysType(tyInt)
+  result = newTypeS(tyRange, c)
+  result.sons = @[intType]
+  result.n = newNode(nkRange, n.info, @[
+    newIntTypeNode(nkIntLit, 0, intType),
+    makeStaticExpr(c, n.nMinusOne)])
+
+template rangeHasStaticIf*(t: PType): bool =
+  # this accepts the ranges's node
+  t.n[1].kind == nkStaticExpr
+
+template getStaticTypeFromRange*(t: PType): PType =
+  t.n[1][0][1].typ
 
 proc newTypeS(kind: TTypeKind, c: PContext): PType =
   result = newType(kind, getCurrOwner())
@@ -272,7 +298,7 @@ proc makeRangeType*(c: PContext; first, last: BiggestInt;
   addSonSkipIntLit(result, intType) # basetype of range
 
 proc markIndirect*(c: PContext, s: PSym) {.inline.} =
-  if s.kind in {skProc, skConverter, skMethod, skIterator}:
+  if s.kind in {skProc, skConverter, skMethod, skIterator, skClosureIterator}:
     incl(s.flags, sfAddrTaken)
     # XXX add to 'c' for global analysis
 
diff --git a/compiler/semdestruct.nim b/compiler/semdestruct.nim
index fb05826cb..791bef823 100644
--- a/compiler/semdestruct.nim
+++ b/compiler/semdestruct.nim
@@ -55,7 +55,9 @@ proc doDestructorStuff(c: PContext, s: PSym, n: PNode) =
             useSym(destructableT.destructor),
             n.sons[paramsPos][1][0]]))
 
-proc destroyField(c: PContext, field: PSym, holder: PNode): PNode =
+proc destroyFieldOrFields(c: PContext, field: PNode, holder: PNode): PNode
+
+proc destroySym(c: PContext, field: PSym, holder: PNode): PNode =
   let destructableT = instantiateDestructor(c, field.typ)
   if destructableT != nil:
     result = newNode(nkCall, field.info, @[
@@ -70,56 +72,49 @@ proc destroyCase(c: PContext, n: PNode, holder: PNode): PNode =
   for i in countup(1, n.len - 1):
     # of A, B:
     var caseBranch = newNode(n[i].kind, n[i].info, n[i].sons[0 .. -2])
-    let recList = n[i].lastSon
-    var destroyRecList = newNode(nkStmtList, n[i].info, @[])
-    template addField(f: expr): stmt =
-      let stmt = destroyField(c, f, holder)
-      if stmt != nil:
-        destroyRecList.addSon(stmt)
-        inc nonTrivialFields
-        
-    case recList.kind
-    of nkSym:
-      addField(recList.sym)
-    of nkRecList:
-      for j in countup(0, recList.len - 1):
-        addField(recList[j].sym)
+    
+    let stmt = destroyFieldOrFields(c, n[i].lastSon, holder)
+    if stmt == nil:
+      caseBranch.addSon(newNode(nkStmtList, n[i].info, @[]))
     else:
-      internalAssert false
-      
-    caseBranch.addSon(destroyRecList)
+      caseBranch.addSon(stmt)
+      nonTrivialFields += stmt.len
+    
     result.addSon(caseBranch)
+  
   # maybe no fields were destroyed?
   if nonTrivialFields == 0:
     result = nil
- 
+
+proc destroyFieldOrFields(c: PContext, field: PNode, holder: PNode): PNode =
+  template maybeAddLine(e: expr): stmt =
+    let stmt = e
+    if stmt != nil:
+      if result == nil: result = newNode(nkStmtList)
+      result.addSon(stmt)
+
+  case field.kind
+  of nkRecCase:
+    maybeAddLine destroyCase(c, field, holder)
+  of nkSym:
+    maybeAddLine destroySym(c, field.sym, holder)
+  of nkRecList:
+    for son in field:
+      maybeAddLine destroyFieldOrFields(c, son, holder)
+  else:
+    internalAssert false
+
 proc generateDestructor(c: PContext, t: PType): PNode =
   ## generate a destructor for a user-defined object or tuple type
   ## returns nil if the destructor turns out to be trivial
   
-  template addLine(e: expr): stmt =
-    if result == nil: result = newNode(nkStmtList)
-    result.addSon(e)
-
   # XXX: This may be true for some C-imported types such as
   # Tposix_spawnattr
   if t.n == nil or t.n.sons == nil: return
   internalAssert t.n.kind == nkRecList
   let destructedObj = newIdentNode(destructorParam, unknownLineInfo())
   # call the destructods of all fields
-  for s in countup(0, t.n.sons.len - 1):
-    case t.n.sons[s].kind
-    of nkRecCase:
-      let stmt = destroyCase(c, t.n.sons[s], destructedObj)
-      if stmt != nil: addLine(stmt)
-    of nkSym:
-      let stmt = destroyField(c, t.n.sons[s].sym, destructedObj)
-      if stmt != nil: addLine(stmt)
-    else:
-      # XXX just skip it for now so that the compiler doesn't crash, but
-      # please zahary fix it! arbitrary nesting of nkRecList/nkRecCase is
-      # possible. Any thread example seems to trigger this. 
-      discard
+  result = destroyFieldOrFields(c, t.n, destructedObj)
   # base classes' destructors will be automatically called by
   # semProcAux for both auto-generated and user-defined destructors
 
diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim
index a8a16672d..1fd9075e8 100644
--- a/compiler/semexprs.nim
+++ b/compiler/semexprs.nim
@@ -21,7 +21,7 @@ proc semFieldAccess(c: PContext, n: PNode, flags: TExprFlags = {}): PNode
 
 proc semOperand(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
   # same as 'semExprWithType' but doesn't check for proc vars
-  result = semExpr(c, n, flags)
+  result = semExpr(c, n, flags + {efOperand})
   if result.kind == nkEmpty: 
     # do not produce another redundant error message:
     #raiseRecoverableError("")
@@ -117,10 +117,12 @@ proc semSym(c: PContext, n: PNode, s: PSym, flags: TExprFlags): PNode =
     elif s.ast != nil:
       result = semExpr(c, s.ast)
     else:
-      internalError(n.info, "no default for")
-      result = emptyNode
+      n.typ = s.typ
+      return n
   of skType:
     markUsed(n, s)
+    if s.typ.kind == tyStatic and s.typ.n != nil:
+      return s.typ.n
     result = newSymNode(s, n.info)
     result.typ = makeTypeDesc(c, s.typ)
   else:
@@ -191,20 +193,47 @@ proc isCastable(dst, src: PType): bool =
 proc isSymChoice(n: PNode): bool {.inline.} =
   result = n.kind in nkSymChoices
 
+proc maybeLiftType(t: var PType, c: PContext, info: TLineInfo) =
+  # XXX: liftParamType started to perform addDecl
+  # we could do that instead in semTypeNode by snooping for added
+  # gnrc. params, then it won't be necessary to open a new scope here
+  openScope(c)
+  var lifted = liftParamType(c, skType, newNodeI(nkArgList, info),
+                         t, ":anon", info)
+  closeScope(c)
+  if lifted != nil: t = lifted
+
 proc semConv(c: PContext, n: PNode): PNode =
   if sonsLen(n) != 2:
     localError(n.info, errConvNeedsOneArg)
     return n
+
   result = newNodeI(nkConv, n.info)
-  result.typ = semTypeNode(c, n.sons[0], nil).skipTypes({tyGenericInst})
-  addSon(result, copyTree(n.sons[0]))
-  addSon(result, semExprWithType(c, n.sons[1]))
-  var op = result.sons[1]
+  var targetType = semTypeNode(c, n.sons[0], nil)
+  maybeLiftType(targetType, c, n[0].info)
+  result.addSon copyTree(n.sons[0])
+  var op = semExprWithType(c, n.sons[1])
+  
+  if targetType.isMetaType:
+    let final = inferWithMetatype(c, targetType, op, true)
+    result.addSon final
+    result.typ = final.typ
+    return
+
+  result.typ = targetType
+  addSon(result, op)
   
   if not isSymChoice(op):
     let status = checkConvertible(c, result.typ, op.typ)
     case status
-    of convOK: discard
+    of convOK:
+      # handle SomeProcType(SomeGenericProc)
+      # XXX: This needs fixing. checkConvertible uses typeRel internally, but
+      # doesn't bother to perform the work done in paramTypeMatchAux/fitNode
+      # so we are redoing the typeRel work here. Why does semConv exist as a
+      # separate proc from fitNode?
+      if op.kind == nkSym and op.sym.isGenericRoutine:
+        result.sons[1] = fitNode(c, result.typ, result.sons[1])
     of convNotNeedeed:
       message(n.info, hintConvFromXtoItselfNotNeeded, result.typ.typeToString)
     of convNotLegal:
@@ -214,7 +243,7 @@ proc semConv(c: PContext, n: PNode): PNode =
     for i in countup(0, sonsLen(op) - 1):
       let it = op.sons[i]
       let status = checkConvertible(c, result.typ, it.typ)
-      if status == convOK:
+      if status in {convOK, convNotNeedeed}:
         markUsed(n, it.sym)
         markIndirect(c, it.sym)
         return it
@@ -316,16 +345,9 @@ proc isOpImpl(c: PContext, n: PNode): PNode =
       result = newIntNode(nkIntLit, ord(t.kind == tyProc and
                                         t.callConv == ccClosure and 
                                         tfIterator notin t.flags))
-    of "iterator":
-      let t = skipTypes(t1, abstractRange)
-      result = newIntNode(nkIntLit, ord(t.kind == tyProc and
-                                        t.callConv == ccClosure and 
-                                        tfIterator in t.flags))
   else:
     var t2 = n[2].typ.skipTypes({tyTypeDesc})
-    let lifted = liftParamType(c, skType, newNodeI(nkArgList, n.info),
-                               t2, ":anon", n.info)
-    if lifted != nil: t2 = lifted
+    maybeLiftType(t2, c, n.info)
     var m: TCandidate
     initCandidate(c, m, t2)
     let match = typeRel(m, t2, t1) != isNone
@@ -339,22 +361,21 @@ proc semIs(c: PContext, n: PNode): PNode =
 
   result = n
   n.typ = getSysType(tyBool)
-  
-  n.sons[1] = semExprWithType(c, n[1], {efDetermineType})
-  
+ 
+  n.sons[1] = semExprWithType(c, n[1], {efDetermineType, efWantIterator})
   if n[2].kind notin {nkStrLit..nkTripleStrLit}:
     let t2 = semTypeNode(c, n[2], nil)
     n.sons[2] = newNodeIT(nkType, n[2].info, t2)
 
-  if n[1].typ.kind != tyTypeDesc:
-    n.sons[1] = makeTypeSymNode(c, n[1].typ, n[1].info)
-  elif n[1].typ.sonsLen == 0:
+  let lhsType = n[1].typ
+  if lhsType.kind != tyTypeDesc:
+    n.sons[1] = makeTypeSymNode(c, lhsType, n[1].info)
+  elif lhsType.base.kind == tyNone:
     # this is a typedesc variable, leave for evals
     return
 
-  let t1 = n[1].typ.sons[0]
   # BUGFIX: don't evaluate this too early: ``T is void``
-  if not containsGenericType(t1): result = isOpImpl(c, n)
+  if not n[1].typ.base.containsGenericType: result = isOpImpl(c, n)
 
 proc semOpAux(c: PContext, n: PNode) =
   const flags = {efDetermineType}
@@ -611,7 +632,19 @@ proc evalAtCompileTime(c: PContext, n: PNode): PNode =
       if result.isNil: result = n
       else: return result
     result.typ = semfold.getIntervalType(callee.magic, call)
-    
+  
+  block maybeLabelAsStatic:
+    # XXX: temporary work-around needed for tlateboundstatic.
+    # This is certainly not correct, but it will get the job
+    # done until we have a more robust infrastructure for
+    # implicit statics.
+    if n.len > 1:
+      for i in 1 .. <n.len:
+        if n[i].typ.kind != tyStatic or tfUnresolved notin n[i].typ.flags:
+          break maybeLabelAsStatic
+      n.typ = newTypeWithSons(c, tyStatic, @[n.typ])
+      n.typ.flags.incl tfUnresolved
+
   # optimization pass: not necessary for correctness of the semantic pass
   if {sfNoSideEffect, sfCompileTime} * callee.flags != {} and
      {sfForward, sfImportc} * callee.flags == {}:
@@ -635,9 +668,11 @@ proc evalAtCompileTime(c: PContext, n: PNode): PNode =
       result = evalStaticExpr(c.module, call, c.p.owner)
       if result.isNil: 
         localError(n.info, errCannotInterpretNodeX, renderTree(call))
+      else: result = fixupTypeAfterEval(c, result, n)
     else:
       result = evalConstExpr(c.module, call)
       if result.isNil: result = n
+      else: result = fixupTypeAfterEval(c, result, n)
     #if result != n:
     #  echo "SUCCESS evaluated at compile time: ", call.renderTree
 
@@ -647,16 +682,18 @@ proc semStaticExpr(c: PContext, n: PNode): PNode =
   if result.isNil:
     localError(n.info, errCannotInterpretNodeX, renderTree(n))
     result = emptyNode
+  else:
+    result = fixupTypeAfterEval(c, result, a)
 
 proc semOverloadedCallAnalyseEffects(c: PContext, n: PNode, nOrig: PNode,
                                      flags: TExprFlags): PNode =
   if flags*{efInTypeof, efWantIterator} != {}:
     # consider: 'for x in pReturningArray()' --> we don't want the restriction
-    # to 'skIterator' anymore; skIterator is preferred in sigmatch already for
-    # typeof support.
+    # to 'skIterators' anymore; skIterators are preferred in sigmatch already 
+    # for typeof support.
     # for ``type(countup(1,3))``, see ``tests/ttoseq``.
     result = semOverloadedCall(c, n, nOrig,
-      {skProc, skMethod, skConverter, skMacro, skTemplate, skIterator})
+      {skProc, skMethod, skConverter, skMacro, skTemplate}+skIterators)
   else:
     result = semOverloadedCall(c, n, nOrig, 
       {skProc, skMethod, skConverter, skMacro, skTemplate})
@@ -669,27 +706,28 @@ proc semOverloadedCallAnalyseEffects(c: PContext, n: PNode, nOrig: PNode,
     case callee.kind
     of skMacro, skTemplate: discard
     else:
-      if (callee.kind == skIterator) and (callee.id == c.p.owner.id): 
+      if (callee.kind in skIterators) and (callee.id == c.p.owner.id): 
         localError(n.info, errRecursiveDependencyX, callee.name.s)
       if sfNoSideEffect notin callee.flags: 
         if {sfImportc, sfSideEffect} * callee.flags != {}:
           incl(c.p.owner.flags, sfSideEffect)
 
 proc semObjConstr(c: PContext, n: PNode, flags: TExprFlags): PNode
-proc semIndirectOp(c: PContext, n: PNode, flags: TExprFlags): PNode = 
+proc semIndirectOp(c: PContext, n: PNode, flags: TExprFlags): PNode =
   result = nil
   checkMinSonsLen(n, 1)
   var prc = n.sons[0]
-  if n.sons[0].kind == nkDotExpr: 
+  if n.sons[0].kind == nkDotExpr:
     checkSonsLen(n.sons[0], 2)
     n.sons[0] = semFieldAccess(c, n.sons[0])
-    if n.sons[0].kind == nkDotCall: 
+    if n.sons[0].kind == nkDotCall:
       # it is a static call!
       result = n.sons[0]
       result.kind = nkCall
+      result.flags.incl nfExplicitCall
       for i in countup(1, sonsLen(n) - 1): addSon(result, n.sons[i])
       return semExpr(c, result, flags)
-  else: 
+  else:
     n.sons[0] = semExpr(c, n.sons[0])
   let nOrig = n.copyTree
   semOpAux(c, n)
@@ -879,7 +917,7 @@ proc lookupInRecordAndBuildCheck(c: PContext, n, r: PNode, field: PIdent,
   of nkSym: 
     if r.sym.name.id == field.id: result = r.sym
   else: illFormedAst(n)
-  
+
 proc makeDeref(n: PNode): PNode = 
   var t = skipTypes(n.typ, {tyGenericInst})
   result = n
@@ -893,6 +931,26 @@ proc makeDeref(n: PNode): PNode =
     addSon(result, a)
     t = skipTypes(t.sons[0], {tyGenericInst})
 
+const
+  tyTypeParamsHolders = {tyGenericInst, tyCompositeTypeClass}
+  tyDotOpTransparent = {tyVar, tyPtr, tyRef}
+
+proc readTypeParameter(c: PContext, typ: PType,
+                       paramName: PIdent, info: TLineInfo): PNode =
+  let ty = if typ.kind == tyGenericInst: typ.skipGenericAlias
+           else: (internalAssert(typ.kind == tyCompositeTypeClass); typ.sons[1])
+  
+  let tbody = ty.sons[0]
+  for s in countup(0, tbody.len-2):
+    let tParam = tbody.sons[s]
+    if tParam.sym.name == paramName:
+      let rawTyp = ty.sons[s + 1]
+      if rawTyp.kind == tyStatic:
+        return rawTyp.n
+      else:
+        let foundTyp = makeTypeDesc(c, rawTyp)
+        return newSymNode(copySym(tParam.sym).linkTo(foundTyp), info)
+
 proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
   ## returns nil if it's not a built-in field access
   checkSonsLen(n, 2)
@@ -910,8 +968,9 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
   var ty = n.sons[0].typ
   var f: PSym = nil
   result = nil
-  if isTypeExpr(n.sons[0]) or ty.kind == tyTypeDesc and ty.len == 1:
-    if ty.kind == tyTypeDesc: ty = ty.sons[0]
+  if isTypeExpr(n.sons[0]) or (ty.kind == tyTypeDesc and ty.base.kind != tyNone):
+    if ty.kind == tyTypeDesc: ty = ty.base
+    ty = ty.skipTypes(tyDotOpTransparent)
     case ty.kind
     of tyEnum:
       # look up if the identifier belongs to the enum:
@@ -919,28 +978,17 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
         f = getSymFromList(ty.n, i)
         if f != nil: break 
         ty = ty.sons[0]         # enum inheritance
-      if f != nil: 
+      if f != nil:
         result = newSymNode(f)
         result.info = n.info
         result.typ = ty
         markUsed(n, f)
         return
-    of tyGenericInst:
-      assert ty.sons[0].kind == tyGenericBody
-      let tbody = ty.sons[0]
-      for s in countup(0, tbody.len-2):
-        let tParam = tbody.sons[s]
-        if tParam.sym.name == i:
-          let rawTyp = ty.sons[s + 1]
-          if rawTyp.kind == tyStatic:
-            return rawTyp.n
-          else:
-            let foundTyp = makeTypeDesc(c, rawTyp)
-            return newSymNode(copySym(tParam.sym).linkTo(foundTyp), n.info)
-      return
+    of tyTypeParamsHolders:
+      return readTypeParameter(c, ty, i, n.info)
     of tyObject, tyTuple:
       if ty.n.kind == nkRecList:
-        for field in ty.n.sons:
+        for field in ty.n:
           if field.sym.name == i:
             n.typ = newTypeWithSons(c, tyFieldAccessor, @[ty, field.sym.typ])
             n.typ.n = copyTree(n)
@@ -952,15 +1000,16 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
     # XXX: This is probably not relevant any more
     # reset to prevent 'nil' bug: see "tests/reject/tenumitems.nim":
     ty = n.sons[0].typ
-    
+    return nil
   ty = skipTypes(ty, {tyGenericInst, tyVar, tyPtr, tyRef})
+  while tfBorrowDot in ty.flags: ty = ty.skipTypes({tyDistinct})
   var check: PNode = nil
-  if ty.kind == tyObject: 
-    while true: 
+  if ty.kind == tyObject:
+    while true:
       check = nil
       f = lookupInRecordAndBuildCheck(c, n, ty.n, i, check)
-      if f != nil: break 
-      if ty.sons[0] == nil: break 
+      if f != nil: break
+      if ty.sons[0] == nil: break
       ty = skipTypes(ty.sons[0], {tyGenericInst})
     if f != nil:
       if fieldVisible(c, f):
@@ -984,6 +1033,12 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
       n.typ = f.typ
       result = n
 
+  # we didn't find any field, let's look for a generic param
+  if result == nil:
+    let t = n.sons[0].typ.skipTypes(tyDotOpTransparent)
+    if t.kind in tyTypeParamsHolders:
+      result = readTypeParameter(c, t, i, n.info)
+
 proc dotTransformation(c: PContext, n: PNode): PNode =
   if isSymChoice(n.sons[1]):
     result = newNodeI(nkDotCall, n.info)
@@ -992,7 +1047,7 @@ proc dotTransformation(c: PContext, n: PNode): PNode =
   else:
     var i = considerAcc(n.sons[1])
     result = newNodeI(nkDotCall, n.info)
-    result.flags.incl nfDelegate
+    result.flags.incl nfDotField
     addSon(result, newIdentNode(i, n[1].info))
     addSon(result, copyTree(n[0]))
   
@@ -1075,12 +1130,13 @@ proc semArrayAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
 
 proc propertyWriteAccess(c: PContext, n, nOrig, a: PNode): PNode =
   var id = considerAcc(a[1])
-  let setterId = newIdentNode(getIdent(id.s & '='), n.info)
+  var setterId = newIdentNode(getIdent(id.s & '='), n.info)
   # a[0] is already checked for semantics, that does ``builtinFieldAccess``
   # this is ugly. XXX Semantic checking should use the ``nfSem`` flag for
   # nodes?
   let aOrig = nOrig[0]
   result = newNode(nkCall, n.info, sons = @[setterId, a[0], semExpr(c, n[1])])
+  result.flags.incl nfDotSetter
   let orig = newNode(nkCall, n.info, sons = @[setterId, aOrig[0], nOrig[1]])
   result = semOverloadedCallAnalyseEffects(c, result, orig, {})
   
@@ -1112,6 +1168,9 @@ proc asgnToResultVar(c: PContext, n, le, ri: PNode) {.inline.} =
       n.sons[0] = x # 'result[]' --> 'result'
       n.sons[1] = takeImplicitAddr(c, ri)
 
+template resultTypeIsInferrable(typ: PType): expr =
+  typ.isMetaType and typ.kind != tyTypeDesc
+
 proc semAsgn(c: PContext, n: PNode): PNode =
   checkSonsLen(n, 2)
   var a = n.sons[0]
@@ -1163,7 +1222,7 @@ proc semAsgn(c: PContext, n: PNode): PNode =
         if lhsIsResult: {efAllowDestructor} else: {})
     if lhsIsResult:
       n.typ = enforceVoidContext
-      if lhs.sym.typ.isMetaType and lhs.sym.typ.kind != tyTypeDesc:
+      if c.p.owner.kind != skMacro and resultTypeIsInferrable(lhs.sym.typ):
         if cmpTypes(c, lhs.typ, rhs.typ) == isGeneric:
           internalAssert c.p.resultSym != nil
           lhs.typ = rhs.typ
@@ -1181,7 +1240,7 @@ proc semReturn(c: PContext, n: PNode): PNode =
   result = n
   checkSonsLen(n, 1)
   if c.p.owner.kind in {skConverter, skMethod, skProc, skMacro} or
-     (c.p.owner.kind == skIterator and c.p.owner.typ.callConv == ccClosure):
+     c.p.owner.kind == skClosureIterator:
     if n.sons[0].kind != nkEmpty:
       # transform ``return expr`` to ``result = expr; return``
       if c.p.resultSym != nil: 
@@ -1199,6 +1258,7 @@ proc semReturn(c: PContext, n: PNode): PNode =
 
 proc semProcBody(c: PContext, n: PNode): PNode =
   openScope(c)
+  
   result = semExpr(c, n)
   if c.p.resultSym != nil and not isEmptyType(result.typ):
     # transform ``expr`` to ``result = expr``, but not if the expr is already
@@ -1222,6 +1282,11 @@ proc semProcBody(c: PContext, n: PNode): PNode =
       result = semAsgn(c, a)
   else:
     discardCheck(c, result)
+  
+  if c.p.owner.kind notin {skMacro, skTemplate} and
+     c.p.resultSym != nil and c.p.resultSym.typ.isMetaType:
+    localError(c.p.resultSym.info, errCannotInferReturnType)
+
   closeScope(c)
 
 proc semYieldVarResult(c: PContext, n: PNode, restype: PType) =
@@ -1246,17 +1311,28 @@ proc semYieldVarResult(c: PContext, n: PNode, restype: PType) =
 proc semYield(c: PContext, n: PNode): PNode =
   result = n
   checkSonsLen(n, 1)
-  if c.p.owner == nil or c.p.owner.kind != skIterator:
+  if c.p.owner == nil or c.p.owner.kind notin skIterators:
     localError(n.info, errYieldNotAllowedHere)
   elif c.p.inTryStmt > 0 and c.p.owner.typ.callConv != ccInline:
     localError(n.info, errYieldNotAllowedInTryStmt)
   elif n.sons[0].kind != nkEmpty:
     n.sons[0] = semExprWithType(c, n.sons[0]) # check for type compatibility:
-    var restype = c.p.owner.typ.sons[0]
+    var iterType = c.p.owner.typ
+    var restype = iterType.sons[0]
     if restype != nil:
-      n.sons[0] = fitNode(c, restype, n.sons[0])
+      let adjustedRes = if c.p.owner.kind == skIterator: restype.base
+                        else: restype
+      n.sons[0] = fitNode(c, adjustedRes, n.sons[0])
       if n.sons[0].typ == nil: internalError(n.info, "semYield")
-      semYieldVarResult(c, n, restype)
+      
+      if resultTypeIsInferrable(adjustedRes):
+        let inferred = n.sons[0].typ
+        if c.p.owner.kind == skIterator:
+          iterType.sons[0].sons[0] = inferred
+        else:
+          iterType.sons[0] = inferred
+      
+      semYieldVarResult(c, n, adjustedRes)
     else:
       localError(n.info, errCannotReturnExpr)
   elif c.p.owner.typ.sons[0] != nil:
@@ -1337,7 +1413,7 @@ proc expectString(c: PContext, n: PNode): string =
     localError(n.info, errStringLiteralExpected)
 
 proc getMagicSym(magic: TMagic): PSym =
-  result = newSym(skProc, getIdent($magic), getCurrOwner(), gCodegenLineInfo)
+  result = newSym(skProc, getIdent($magic), systemModule, gCodegenLineInfo)
   result.magic = magic
 
 proc newAnonSym(kind: TSymKind, info: TLineInfo,
@@ -1405,9 +1481,8 @@ proc processQuotations(n: var PNode, op: string,
   elif n.kind == nkAccQuoted and op == "``":
     returnQuote n[0]
  
-  if not n.isAtom:
-    for i in 0 .. <n.len:
-      processQuotations(n.sons[i], op, quotes, ids)
+  for i in 0 .. <n.safeLen:
+    processQuotations(n.sons[i], op, quotes, ids)
 
 proc semQuoteAst(c: PContext, n: PNode): PNode =
   internalAssert n.len == 2 or n.len == 3
@@ -1770,22 +1845,6 @@ proc semBlock(c: PContext, n: PNode): PNode =
   closeScope(c)
   dec(c.p.nestedBlockCounter)
 
-proc buildCall(n: PNode): PNode =
-  if n.kind == nkDotExpr and n.len == 2:
-    # x.y --> y(x)
-    result = newNodeI(nkCall, n.info, 2)
-    result.sons[0] = n.sons[1]
-    result.sons[1] = n.sons[0]
-  elif n.kind in nkCallKinds and n.sons[0].kind == nkDotExpr:
-    # x.y(a) -> y(x, a)
-    let a = n.sons[0]
-    result = newNodeI(nkCall, n.info, n.len+1)
-    result.sons[0] = a.sons[1]
-    result.sons[1] = a.sons[0]
-    for i in 1 .. <n.len: result.sons[i+1] = n.sons[i]
-  else:
-    result = n
-
 proc doBlockIsStmtList(n: PNode): bool =
   result = n.kind == nkDo and
            n[paramsPos].sonsLen == 1 and
@@ -1832,13 +1891,13 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
     var s = lookUp(c, n)
     semCaptureSym(s, c.p.owner)
     result = semSym(c, n, s, flags)
-    if s.kind in {skProc, skMethod, skIterator, skConverter}:
+    if s.kind in {skProc, skMethod, skConverter}+skIterators:
       #performProcvarCheck(c, n, s)
       result = symChoice(c, n, s, scClosed)
       if result.kind == nkSym:
         markIndirect(c, result.sym)
-        if isGenericRoutine(result.sym):
-          localError(n.info, errInstantiateXExplicitely, s.name.s)
+        # if isGenericRoutine(result.sym):
+        #   localError(n.info, errInstantiateXExplicitely, s.name.s)
   of nkSym:
     # because of the changed symbol binding, this does not mean that we
     # don't have to check the symbol for semantics here again!
@@ -1888,13 +1947,13 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
     message(n.info, warnDeprecated, "bind")
     result = semExpr(c, n.sons[0], flags)
   of nkTypeOfExpr, nkTupleTy, nkRefTy..nkEnumTy, nkStaticTy:
-    var typ = semTypeNode(c, n, nil).skipTypes({tyTypeDesc})
+    var typ = semTypeNode(c, n, nil).skipTypes({tyTypeDesc, tyIter})
     result.typ = makeTypeDesc(c, typ)
     #result = symNodeFromType(c, typ, n.info)
   of nkCall, nkInfix, nkPrefix, nkPostfix, nkCommand, nkCallStrLit: 
     # check if it is an expression macro:
     checkMinSonsLen(n, 1)
-    let mode = if nfDelegate in n.flags: {} else: {checkUndeclared}
+    let mode = if nfDotField in n.flags: {} else: {checkUndeclared}
     var s = qualifiedLookUp(c, n.sons[0], mode)
     if s != nil: 
       if gCmd == cmdPretty and n.sons[0].kind == nkDotExpr:
@@ -1922,7 +1981,7 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
           localError(n.info, errUseQualifier, s.name.s)
         elif s.magic == mNone: result = semDirectOp(c, n, flags)
         else: result = semMagic(c, n, s, flags)
-      of skProc, skMethod, skConverter, skIterator: 
+      of skProc, skMethod, skConverter, skIterators:
         if s.magic == mNone: result = semDirectOp(c, n, flags)
         else: result = semMagic(c, n, s, flags)
       else:
@@ -1933,7 +1992,7 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
       # the 'newSeq[T](x)' bug
       setGenericParams(c, n.sons[0])
       result = semDirectOp(c, n, flags)
-    elif isSymChoice(n.sons[0]) or nfDelegate in n.flags:
+    elif isSymChoice(n.sons[0]) or nfDotField in n.flags:
       result = semDirectOp(c, n, flags)
     else:
       result = semIndirectOp(c, n, flags)
@@ -1946,7 +2005,8 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
   of nkBracketExpr:
     checkMinSonsLen(n, 1)
     var s = qualifiedLookUp(c, n.sons[0], {checkUndeclared})
-    if s != nil and s.kind in {skProc, skMethod, skConverter, skIterator}: 
+    if (s != nil and s.kind in {skProc, skMethod, skConverter}+skIterators) or
+        n[0].kind in nkSymChoices:
       # type parameters: partial generic specialization
       n.sons[0] = semSymGenericInstantiation(c, n.sons[0], s)
       result = explicitGenericInstantiation(c, n, s)
diff --git a/compiler/semfold.nim b/compiler/semfold.nim
index 4740ddcb3..925a80832 100644
--- a/compiler/semfold.nim
+++ b/compiler/semfold.nim
@@ -537,7 +537,7 @@ proc foldArrayAccess(m: PSym, n: PNode): PNode =
       if result.kind == nkExprColonExpr: result = result.sons[1]
     else:
       localError(n.info, errIndexOutOfBounds)
-  of nkBracket, nkMetaNode: 
+  of nkBracket: 
     if (idx >= 0) and (idx < sonsLen(x)): result = x.sons[int(idx)]
     else: localError(n.info, errIndexOutOfBounds)
   of nkStrLit..nkTripleStrLit: 
diff --git a/compiler/semgnrc.nim b/compiler/semgnrc.nim
index b21d851c9..ffc1a43b2 100644
--- a/compiler/semgnrc.nim
+++ b/compiler/semgnrc.nim
@@ -42,7 +42,7 @@ proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym): PNode =
   of skUnknown: 
     # Introduced in this pass! Leave it as an identifier.
     result = n
-  of skProc, skMethod, skIterator, skConverter: 
+  of skProc, skMethod, skIterators, skConverter:
     result = symChoice(c, n, s, scOpen)
   of skTemplate:
     if macroToExpand(s):
@@ -141,7 +141,7 @@ proc semGenericStmt(c: PContext, n: PNode,
         # symbol lookup ...
       of skUnknown, skParam: 
         # Leave it as an identifier.
-      of skProc, skMethod, skIterator, skConverter: 
+      of skProc, skMethod, skIterators, skConverter:
         result.sons[0] = symChoice(c, n.sons[0], s, scOption)
         first = 1
       of skGenericParam:
diff --git a/compiler/seminst.nim b/compiler/seminst.nim
index 8faf1d21a..a5149a842 100644
--- a/compiler/seminst.nim
+++ b/compiler/seminst.nim
@@ -15,12 +15,11 @@ proc instantiateGenericParamList(c: PContext, n: PNode, pt: TIdTable,
   if n.kind != nkGenericParams: 
     internalError(n.info, "instantiateGenericParamList; no generic params")
   newSeq(entry.concreteTypes, n.len)
-  for i in countup(0, n.len - 1):
-    var a = n.sons[i]
+  for i, a in n.pairs:
     if a.kind != nkSym: 
       internalError(a.info, "instantiateGenericParamList; no symbol")
     var q = a.sym
-    if q.typ.kind notin {tyTypeDesc, tyGenericParam, tyStatic}+tyTypeClasses:
+    if q.typ.kind notin {tyTypeDesc, tyGenericParam, tyStatic, tyIter}+tyTypeClasses:
       continue
     var s = newSym(skType, q.name, getCurrOwner(), q.info)
     s.flags = s.flags + {sfUsed, sfFromGeneric}
@@ -86,19 +85,21 @@ proc freshGenSyms(n: PNode, owner: PSym, symMap: var TIdTable) =
 
 proc addParamOrResult(c: PContext, param: PSym, kind: TSymKind)
 
+proc addProcDecls(c: PContext, fn: PSym) =
+  # get the proc itself in scope (e.g. for recursion)
+  addDecl(c, fn)
+
+  for i in 1 .. <fn.typ.n.len:
+    var param = fn.typ.n.sons[i].sym
+    param.owner = fn
+    addParamOrResult(c, param, fn.kind)
+  
+  maybeAddResult(c, fn, fn.ast)
+
 proc instantiateBody(c: PContext, n: PNode, result: PSym) =
   if n.sons[bodyPos].kind != nkEmpty:
     inc c.inGenericInst
     # add it here, so that recursive generic procs are possible:
-    addDecl(c, result)
-    pushProcCon(c, result)
-    # add params to scope
-    for i in 1 .. <result.typ.n.len:
-      var param = result.typ.n.sons[i].sym
-      param.owner = result
-      addParamOrResult(c, param, result.kind)
-    # debug result.typ.n
-    maybeAddResult(c, result, n)
     var b = n.sons[bodyPos]
     var symMap: TIdTable
     initIdTable symMap
@@ -108,7 +109,6 @@ proc instantiateBody(c: PContext, n: PNode, result: PSym) =
     n.sons[bodyPos] = transformBody(c.module, b, result)
     #echo "code instantiated ", result.name.s
     excl(result.flags, sfForward)
-    popProcCon(c)
     dec c.inGenericInst
 
 proc fixupInstantiatedSymbols(c: PContext, s: PSym) =
@@ -145,11 +145,56 @@ proc instGenericContainer(c: PContext, info: TLineInfo, header: PType,
 proc instGenericContainer(c: PContext, n: PNode, header: PType): PType =
   result = instGenericContainer(c, n.info, header)
 
+proc instantiateProcType(c: PContext, pt: TIdTable,
+                          prc: PSym, info: TLineInfo) =
+  # XXX: Instantiates a generic proc signature, while at the same
+  # time adding the instantiated proc params into the current scope.
+  # This is necessary, because the instantiation process may refer to
+  # these params in situations like this:
+  # proc foo[Container](a: Container, b: a.type.Item): type(b.x)
+  #
+  # Alas, doing this here is probably not enough, because another
+  # proc signature could appear in the params:
+  # proc foo[T](a: proc (x: T, b: type(x.y))
+  #   
+  # The solution would be to move this logic into semtypinst, but
+  # at this point semtypinst have to become part of sem, because it
+  # will need to use openScope, addDecl, etc
+  #
+  addDecl(c, prc)
+  
+  pushInfoContext(info)
+  var cl = initTypeVars(c, pt, info)
+  var result = instCopyType(cl, prc.typ)
+  let originalParams = result.n
+  result.n = originalParams.shallowCopy
+  
+  for i in 1 .. <result.len:
+    result.sons[i] = replaceTypeVarsT(cl, result.sons[i])
+    propagateToOwner(result, result.sons[i])
+    let param = replaceTypeVarsN(cl, originalParams[i])
+    result.n.sons[i] = param
+    if param.kind == nkSym:
+      # XXX: this won't be true for void params
+      # implement pass-through of void params and
+      # the "sort by distance to point" container
+      param.sym.owner = prc
+      addDecl(c, param.sym)
+    
+  result.sons[0] = replaceTypeVarsT(cl, result.sons[0])
+  result.n.sons[0] = originalParams[0].copyTree
+  
+  eraseVoidParams(result)
+  skipIntLiteralParams(result)
+ 
+  prc.typ = result
+  maybeAddResult(c, prc, prc.ast)
+  popInfoContext()
+
 proc generateInstance(c: PContext, fn: PSym, pt: TIdTable,
                       info: TLineInfo): PSym =
   # no need to instantiate generic templates/macros:
   if fn.kind in {skTemplate, skMacro}: return fn
- 
   # generates an instantiated proc
   if c.instCounter > 1000: internalError(fn.ast.info, "nesting too deep")
   inc(c.instCounter)
@@ -173,7 +218,8 @@ proc generateInstance(c: PContext, fn: PSym, pt: TIdTable,
   var entry = TInstantiation.new
   entry.sym = result
   instantiateGenericParamList(c, n.sons[genericParamsPos], pt, entry[])
-  result.typ = generateTypeInstance(c, pt, info, fn.typ)
+  pushProcCon(c, result)
+  instantiateProcType(c, pt, result, info)
   n.sons[genericParamsPos] = ast.emptyNode
   var oldPrc = genericCacheGet(fn, entry[])
   if oldPrc == nil:
@@ -183,12 +229,12 @@ proc generateInstance(c: PContext, fn: PSym, pt: TIdTable,
       pragma(c, result, n.sons[pragmasPos], allRoutinePragmas)
     if isNil(n.sons[bodyPos]):
       n.sons[bodyPos] = copyTree(fn.getBody)
-    if fn.kind != skTemplate:
-      instantiateBody(c, n, result)
-      sideEffectsCheck(c, result)
+    instantiateBody(c, n, result)
+    sideEffectsCheck(c, result)
     paramsTypeCheck(c, result.typ)
   else:
     result = oldPrc
+  popProcCon(c)
   popInfoContext()
   closeScope(c)           # close scope for parameters
   popOwner()
diff --git a/compiler/sempass2.nim b/compiler/sempass2.nim
index fb266ae3a..a00325277 100644
--- a/compiler/sempass2.nim
+++ b/compiler/sempass2.nim
@@ -84,10 +84,10 @@ proc initVar(a: PEffects, n: PNode) =
 proc initVarViaNew(a: PEffects, n: PNode) =
   if n.kind != nkSym: return
   let s = n.sym
-  if {tfNeedsInit, tfNotNil} * s.typ.flags == {tfNotNil}:
+  if {tfNeedsInit, tfNotNil} * s.typ.flags <= {tfNotNil}:
     # 'x' is not nil, but that doesn't mean it's not nil children
     # are initialized:
-    initVarViaNew(a, n)
+    initVar(a, n)
 
 proc useVar(a: PEffects, n: PNode) =
   let s = n.sym
@@ -466,8 +466,7 @@ proc track(tracked: PEffects, n: PNode) =
         mergeEffects(tracked, effectList.sons[exceptionEffects], n)
         mergeTags(tracked, effectList.sons[tagEffects], n)
     for i in 1 .. <len(n): trackOperand(tracked, n.sons[i], paramType(op, i))
-    if a.kind == nkSym and a.sym.magic in {mNew, mNewFinalize, 
-                                           mNewSeq, mShallowCopy}:
+    if a.kind == nkSym and a.sym.magic in {mNew, mNewFinalize, mNewSeq}:
       # may not look like an assignment, but it is:
       initVarViaNew(tracked, n.sons[1])
     for i in 0 .. <safeLen(n):
@@ -477,7 +476,6 @@ proc track(tracked: PEffects, n: PNode) =
     if warnProveField in gNotes: checkFieldAccess(tracked.guards, n)
   of nkTryStmt: trackTryStmt(tracked, n)
   of nkPragma: trackPragmaStmt(tracked, n)
-  of nkMacroDef, nkTemplateDef: discard
   of nkAsgn, nkFastAsgn:
     track(tracked, n.sons[1])
     initVar(tracked, n.sons[0])
@@ -527,7 +525,9 @@ proc track(tracked: PEffects, n: PNode) =
       if sfDiscriminant in x.sons[0].sym.flags:
         addDiscriminantFact(tracked.guards, x)
     setLen(tracked.guards, oldFacts)
-  of nkTypeSection: discard
+  of nkTypeSection, nkProcDef, nkConverterDef, nkMethodDef, nkIteratorDef,
+      nkMacroDef, nkTemplateDef:
+    discard
   else:
     for i in 0 .. <safeLen(n): track(tracked, n.sons[i])
 
@@ -581,22 +581,26 @@ proc setEffectsForProcType*(t: PType, n: PNode) =
     if not isNil(tagsSpec):
       effects.sons[tagEffects] = tagsSpec
 
+proc initEffects(effects: PNode; s: PSym; t: var TEffects) =
+  newSeq(effects.sons, effectListLen)
+  effects.sons[exceptionEffects] = newNodeI(nkArgList, s.info)
+  effects.sons[tagEffects] = newNodeI(nkArgList, s.info)
+  
+  t.exc = effects.sons[exceptionEffects]
+  t.tags = effects.sons[tagEffects]
+  t.owner = s
+  t.init = @[]
+  t.guards = @[]
+  
 proc trackProc*(s: PSym, body: PNode) =
   var effects = s.typ.n.sons[0]
   internalAssert effects.kind == nkEffectList
   # effects already computed?
   if sfForward in s.flags: return
   if effects.len == effectListLen: return
-  newSeq(effects.sons, effectListLen)
-  effects.sons[exceptionEffects] = newNodeI(nkArgList, body.info)
-  effects.sons[tagEffects] = newNodeI(nkArgList, body.info)
   
   var t: TEffects
-  t.exc = effects.sons[exceptionEffects]
-  t.tags = effects.sons[tagEffects]
-  t.owner = s
-  t.init = @[]
-  t.guards = @[]
+  initEffects(effects, s, t)
   track(t, body)
   
   if not isEmptyType(s.typ.sons[0]) and tfNeedsInit in s.typ.sons[0].flags and
@@ -619,3 +623,12 @@ proc trackProc*(s: PSym, body: PNode) =
     # after the check, use the formal spec:
     effects.sons[tagEffects] = tagsSpec
     
+proc trackTopLevelStmt*(module: PSym; n: PNode) =
+  if n.kind in {nkPragma, nkMacroDef, nkTemplateDef, nkProcDef,
+                nkTypeSection, nkConverterDef, nkMethodDef, nkIteratorDef}:
+    return
+  var effects = newNode(nkEffectList, n.info)
+  var t: TEffects
+  initEffects(effects, module, t)
+
+  track(t, n)
diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim
index 0871b7fb7..c31a8a06d 100644
--- a/compiler/semstmts.nim
+++ b/compiler/semstmts.nim
@@ -12,9 +12,6 @@
 
 var enforceVoidContext = PType(kind: tyStmt)
 
-proc semCommand(c: PContext, n: PNode): PNode =
-  result = semExprNoType(c, n)
-  
 proc semDiscard(c: PContext, n: PNode): PNode = 
   result = n
   checkSonsLen(n, 1)
@@ -76,8 +73,8 @@ proc performProcvarCheck(c: PContext, n: PNode, s: PSym) =
 
 proc semProcvarCheck(c: PContext, n: PNode) =
   let n = n.skipConv
-  if n.kind == nkSym and n.sym.kind in {skProc, skMethod, skIterator,
-                                        skConverter}:
+  if n.kind == nkSym and n.sym.kind in {skProc, skMethod, skConverter,
+                                        skIterator, skClosureIterator}:
     performProcvarCheck(c, n, n.sym)
 
 proc semProc(c: PContext, n: PNode): PNode
@@ -126,13 +123,14 @@ proc implicitlyDiscardable(n: PNode): bool =
 proc fixNilType(n: PNode) =
   if isAtom(n):
     if n.kind != nkNilLit and n.typ != nil:
-      localError(n.info, errDiscardValue)
+      localError(n.info, errDiscardValueX, n.typ.typeToString)
   elif n.kind in {nkStmtList, nkStmtListExpr}:
     n.kind = nkStmtList
     for it in n: fixNilType(it)
   n.typ = nil
 
 proc discardCheck(c: PContext, result: PNode) =
+  if c.inTypeClass > 0: return
   if result.typ != nil and result.typ.kind notin {tyStmt, tyEmpty}:
     if result.kind == nkNilLit:
       result.typ = nil
@@ -143,10 +141,6 @@ proc discardCheck(c: PContext, result: PNode) =
       while n.kind in skipForDiscardable:
         n = n.lastSon
         n.typ = nil
-    elif c.inTypeClass > 0 and result.typ.kind == tyBool:
-      let verdict = semConstExpr(c, result)
-      if verdict.intVal == 0:
-        localError(result.info, "type class predicate failed")
     elif result.typ.kind != tyError and gCmd != cmdInteractive:
       if result.typ.kind == tyNil:
         fixNilType(result)
@@ -154,7 +148,7 @@ proc discardCheck(c: PContext, result: PNode) =
       else:
         var n = result
         while n.kind in skipForDiscardable: n = n.lastSon
-        localError(n.info, errDiscardValue)
+        localError(n.info, errDiscardValueX, result.typ.typeToString)
 
 proc semIf(c: PContext, n: PNode): PNode = 
   result = n
@@ -331,6 +325,7 @@ proc checkNilable(v: PSym) =
 proc semVarOrLet(c: PContext, n: PNode, symkind: TSymKind): PNode = 
   var b: PNode
   result = copyNode(n)
+  var hasCompileTime = false
   for i in countup(0, sonsLen(n)-1): 
     var a = n.sons[i]
     if gCmd == cmdIdeTools: suggestStmt(c, a)
@@ -349,7 +344,12 @@ proc semVarOrLet(c: PContext, n: PNode, symkind: TSymKind): PNode =
       # BUGFIX: ``fitNode`` is needed here!
       # check type compability between def.typ and typ:
       if typ != nil: def = fitNode(c, typ, def)
-      else: typ = skipIntLit(def.typ)
+      else:
+        typ = skipIntLit(def.typ)
+        if typ.kind in {tySequence, tyArray, tySet} and
+           typ.lastSon.kind == tyEmpty:
+          localError(def.info, errCannotInferTypeOfTheLiteral,
+                     ($typ.kind).substr(2).toLower)
     else:
       def = ast.emptyNode
       if symkind == skLet: localError(a.info, errLetNeedsInit)
@@ -405,7 +405,9 @@ proc semVarOrLet(c: PContext, n: PNode, symkind: TSymKind): PNode =
         v.typ = tup.sons[j]
         b.sons[j] = newSymNode(v)
       checkNilable(v)
-    
+      if sfCompileTime in v.flags: hasCompileTime = true
+  if hasCompileTime: vm.setupCompileTimeVar(c.module, result)
+
 proc semConst(c: PContext, n: PNode): PNode = 
   result = copyNode(n)
   for i in countup(0, sonsLen(n) - 1): 
@@ -607,7 +609,8 @@ proc symForVar(c: PContext, n: PNode): PSym =
 proc semForVars(c: PContext, n: PNode): PNode =
   result = n
   var length = sonsLen(n)
-  var iter = skipTypes(n.sons[length-2].typ, {tyGenericInst})
+  let iterBase = n.sons[length-2].typ.skipTypes({tyIter})
+  var iter = skipTypes(iterBase, {tyGenericInst})
   # length == 3 means that there is one for loop variable
   # and thus no tuple unpacking:
   if iter.kind != tyTuple or length == 3: 
@@ -617,7 +620,7 @@ proc semForVars(c: PContext, n: PNode): PNode =
       # BUGFIX: don't use `iter` here as that would strip away
       # the ``tyGenericInst``! See ``tests/compile/tgeneric.nim``
       # for an example:
-      v.typ = n.sons[length-2].typ
+      v.typ = iterBase
       n.sons[0] = newSymNode(v)
       if sfGenSym notin v.flags: addForVarDecl(c, v)
     else:
@@ -651,11 +654,19 @@ proc semFor(c: PContext, n: PNode): PNode =
   openScope(c)
   n.sons[length-2] = semExprNoDeref(c, n.sons[length-2], {efWantIterator})
   var call = n.sons[length-2]
-  if call.kind in nkCallKinds and call.sons[0].typ.callConv == ccClosure:
+  let isCallExpr = call.kind in nkCallKinds
+  if isCallExpr and call.sons[0].sym.magic != mNone:
+    if call.sons[0].sym.magic == mOmpParFor:
+      result = semForVars(c, n)
+      result.kind = nkParForStmt
+    else:
+      result = semForFields(c, n, call.sons[0].sym.magic)
+  elif (isCallExpr and call.sons[0].typ.callConv == ccClosure) or
+      call.typ.kind == tyIter:
     # first class iterator:
     result = semForVars(c, n)
-  elif call.kind notin nkCallKinds or call.sons[0].kind != nkSym or
-      call.sons[0].sym.kind != skIterator: 
+  elif not isCallExpr or call.sons[0].kind != nkSym or
+      call.sons[0].sym.kind notin skIterators:
     if length == 3:
       n.sons[length-2] = implicitIterator(c, "items", n.sons[length-2])
     elif length == 4:
@@ -663,12 +674,6 @@ proc semFor(c: PContext, n: PNode): PNode =
     else:
       localError(n.sons[length-2].info, errIteratorExpected)
     result = semForVars(c, n)
-  elif call.sons[0].sym.magic != mNone:
-    if call.sons[0].sym.magic == mOmpParFor:
-      result = semForVars(c, n)
-      result.kind = nkParForStmt
-    else:
-      result = semForFields(c, n, call.sons[0].sym.magic)
   else:
     result = semForVars(c, n)
   # propagate any enforced VoidContext:
@@ -764,6 +769,29 @@ proc typeSectionRightSidePass(c: PContext, n: PNode) =
       s.ast = a
       popOwner()
 
+proc checkForMetaFields(n: PNode) =
+  template checkMeta(t) =
+    if t != nil and t.isMetaType and tfGenericTypeParam notin t.flags:
+      localError(n.info, errTIsNotAConcreteType, t.typeToString)
+  
+  case n.kind
+  of nkRecList, nkRecCase:
+    for s in n: checkForMetaFields(s)
+  of nkOfBranch, nkElse:
+    checkForMetaFields(n.lastSon)
+  of nkSym:
+    let t = n.sym.typ
+    case t.kind
+    of tySequence, tySet, tyArray, tyOpenArray, tyVar, tyPtr, tyRef,
+       tyProc, tyGenericInvokation, tyGenericInst:
+      let start = ord(t.kind in {tyGenericInvokation, tyGenericInst})
+      for i in start .. <t.sons.len:
+        checkMeta(t.sons[i])
+    else:
+      checkMeta(t)
+  else:
+    internalAssert false
+
 proc typeSectionFinalPass(c: PContext, n: PNode) = 
   for i in countup(0, sonsLen(n) - 1): 
     var a = n.sons[i]
@@ -780,6 +808,8 @@ proc typeSectionFinalPass(c: PContext, n: PNode) =
           assignType(s.typ, t)
           s.typ.id = t.id     # same id
       checkConstructedType(s.info, s.typ)
+      if s.typ.kind in {tyObject, tyTuple}:
+        checkForMetaFields(s.typ.n)
     let aa = a.sons[2]
     if aa.kind in {nkRefTy, nkPtrTy} and aa.len == 1 and
        aa.sons[0].kind == nkObjectTy:
@@ -883,12 +913,19 @@ proc semLambda(c: PContext, n: PNode, flags: TExprFlags): PNode =
     s = n[namePos].sym
   pushOwner(s)
   openScope(c)
-  if n.sons[genericParamsPos].kind != nkEmpty:
-    illFormedAst(n)           # process parameters:
+  var gp: PNode
+  if n.sons[genericParamsPos].kind != nkEmpty: 
+    n.sons[genericParamsPos] = semGenericParamList(c, n.sons[genericParamsPos])
+    gp = n.sons[genericParamsPos]
+  else:
+    gp = newNodeI(nkGenericParams, n.info)
+
   if n.sons[paramsPos].kind != nkEmpty:
-    var gp = newNodeI(nkGenericParams, n.info)
     semParamList(c, n.sons[paramsPos], gp, s)
-    paramsTypeCheck(c, s.typ)
+    # paramsTypeCheck(c, s.typ)
+    if sonsLen(gp) > 0 and n.sons[genericParamsPos].kind == nkEmpty:
+      # we have a list of implicit type parameters:
+      n.sons[genericParamsPos] = gp
   else:
     s.typ = newTypeS(tyProc, c)
     rawAddSon(s.typ, nil)
@@ -900,12 +937,15 @@ proc semLambda(c: PContext, n: PNode, flags: TExprFlags): PNode =
       localError(n.sons[bodyPos].info, errImplOfXNotAllowed, s.name.s)
     #if efDetermineType notin flags:
     # XXX not good enough; see tnamedparamanonproc.nim
-    pushProcCon(c, s)
-    addResult(c, s.typ.sons[0], n.info, skProc)
-    let semBody = hloBody(c, semProcBody(c, n.sons[bodyPos]))
-    n.sons[bodyPos] = transformBody(c.module, semBody, s)
-    addResultNode(c, n)
-    popProcCon(c)
+    if gp.len == 0 or (gp.len == 1 and tfRetType in gp[0].typ.flags):
+      pushProcCon(c, s)
+      addResult(c, s.typ.sons[0], n.info, skProc)
+      let semBody = hloBody(c, semProcBody(c, n.sons[bodyPos]))
+      n.sons[bodyPos] = transformBody(c.module, semBody, s)
+      addResultNode(c, n)
+      popProcCon(c)
+    elif efOperand notin flags:
+      localError(n.info, errGenericLambdaNotAllowed)
     sideEffectsCheck(c, s)
   else:
     localError(n.info, errImplOfXexpected, s.name.s)
@@ -913,6 +953,34 @@ proc semLambda(c: PContext, n: PNode, flags: TExprFlags): PNode =
   popOwner()
   result.typ = s.typ
 
+proc semInferredLambda(c: PContext, pt: TIdTable, n: PNode): PNode =
+  var n = n
+  
+  n = replaceTypesInBody(c, pt, n)
+  result = n
+  
+  n.sons[genericParamsPos] = emptyNode
+  n.sons[paramsPos] = n.typ.n
+  
+  openScope(c)
+  var s = n.sons[namePos].sym
+  addParams(c, n.typ.n, skProc)
+  pushProcCon(c, s)
+  addResult(c, n.typ.sons[0], n.info, skProc)
+  let semBody = hloBody(c, semProcBody(c, n.sons[bodyPos]))
+  n.sons[bodyPos] = transformBody(c.module, semBody, n.sons[namePos].sym)
+  addResultNode(c, n)
+  popProcCon(c)
+  closeScope(c)
+  
+  s.ast = result
+
+  # alternative variant (not quite working):
+  # var prc = arg[0].sym
+  # let inferred = c.semGenerateInstance(c, prc, m.bindings, arg.info)
+  # result = inferred.ast
+  # result.kind = arg.kind
+
 proc activate(c: PContext, n: PNode) =
   # XXX: This proc is part of my plan for getting rid of
   # forward declarations. stay tuned.
@@ -927,8 +995,7 @@ proc activate(c: PContext, n: PNode) =
       discard
 
 proc maybeAddResult(c: PContext, s: PSym, n: PNode) =
-  if s.typ.sons[0] != nil and
-      (s.kind != skIterator or s.typ.callConv == ccClosure):
+  if s.typ.sons[0] != nil and s.kind != skIterator:
     addResult(c, s.typ.sons[0], n.info, s.kind)
     addResultNode(c, n)
 
@@ -971,6 +1038,7 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
       return
   else:
     s = n[namePos].sym
+    s.owner = getCurrOwner()
     typeIsDetermined = s.typ == nil
     s.ast = n
     s.scope = c.currentScope
@@ -1003,12 +1071,12 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
     rawAddSon(s.typ, nil)
   if n.sons[patternPos].kind != nkEmpty:
     n.sons[patternPos] = semPattern(c, n.sons[patternPos])
-  if s.kind == skIterator: 
+  if s.kind in skIterators:
     s.typ.flags.incl(tfIterator)
   
   var proto = searchForProc(c, s.scope, s)
-  if proto == nil: 
-    if s.kind == skIterator and isAnon: s.typ.callConv = ccClosure
+  if proto == nil:
+    if s.kind == skClosureIterator: s.typ.callConv = ccClosure
     else: s.typ.callConv = lastOptionEntry(c).defaultCC
     # add it here, so that recursive procs are possible:
     if sfGenSym in s.flags: discard
@@ -1021,7 +1089,7 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
     if n.sons[pragmasPos].kind != nkEmpty:
       pragma(c, s, n.sons[pragmasPos], validPragmas)
     else:
-      implictPragmas(c, s, n, validPragmas)
+      implicitPragmas(c, s, n, validPragmas)
   else: 
     if n.sons[pragmasPos].kind != nkEmpty: 
       localError(n.sons[pragmasPos].info, errPragmaOnlyInHeaderOfProc)
@@ -1068,7 +1136,7 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
         n.sons[bodyPos] = transformBody(c.module, semBody, s)
       popProcCon(c)
     else:
-      if s.typ.sons[0] != nil and kind != skIterator:
+      if s.typ.sons[0] != nil and kind notin skIterators:
         addDecl(c, newSym(skUnknown, getIdent"result", nil, n.info))
       var toBind = initIntSet()
       n.sons[bodyPos] = semGenericStmtScope(c, n.sons[bodyPos], {}, toBind)
@@ -1095,7 +1163,15 @@ proc determineType(c: PContext, s: PSym) =
   discard semProcAux(c, s.ast, s.kind, {}, stepDetermineType)
 
 proc semIterator(c: PContext, n: PNode): PNode =
-  result = semProcAux(c, n, skIterator, iteratorPragmas)
+  let kind = if hasPragma(n[pragmasPos], wClosure) or
+                n[namePos].kind == nkEmpty: skClosureIterator
+             else: skIterator
+  # gensym'ed iterator?
+  if n[namePos].kind == nkSym:
+    # gensym'ed iterators might need to become closure iterators:
+    n[namePos].sym.owner = getCurrOwner()
+    n[namePos].sym.kind = kind
+  result = semProcAux(c, n, kind, iteratorPragmas)
   var s = result.sons[namePos].sym
   var t = s.typ
   if t.sons[0] == nil and s.typ.callConv != ccClosure:
@@ -1247,13 +1323,17 @@ proc semStmtList(c: PContext, n: PNode, flags: TExprFlags): PNode =
       return
     else:
       n.sons[i] = semExpr(c, n.sons[i])
+      if c.inTypeClass > 0 and n[i].typ != nil and n[i].typ.kind == tyBool:
+        let verdict = semConstExpr(c, n[i])
+        if verdict.intVal == 0:
+          localError(result.info, "type class predicate failed")
       if n.sons[i].typ == enforceVoidContext or usesResult(n.sons[i]):
         voidContext = true
         n.typ = enforceVoidContext
-      if i == last and efWantValue in flags:
+      if i == last and (length == 1 or efWantValue in flags):
         n.typ = n.sons[i].typ
         if not isEmptyType(n.typ): n.kind = nkStmtListExpr
-      elif i != last or voidContext or c.inTypeClass > 0:
+      elif i != last or voidContext:
         discardCheck(c, n.sons[i])
       else:
         n.typ = n.sons[i].typ
@@ -1263,8 +1343,8 @@ proc semStmtList(c: PContext, n: PNode, flags: TExprFlags): PNode =
         let (outer, inner) = insertDestructors(c, n.sons[i])
         if outer != nil:
           n.sons[i] = outer
-          for j in countup(i+1, length-1):
-            inner.addSon(semStmt(c, n.sons[j]))
+          var rest = newNode(nkStmtList, n.info, n.sons[i+1 .. length-1])
+          inner.addSon(semStmtList(c, rest, flags))
           n.sons.setLen(i+1)
           return
       of LastBlockStmts: 
diff --git a/compiler/semtempl.nim b/compiler/semtempl.nim
index 5abc3ef33..b71198119 100644
--- a/compiler/semtempl.nim
+++ b/compiler/semtempl.nim
@@ -155,7 +155,11 @@ proc addLocalDecl(c: var TemplCtx, n: var PNode, k: TSymKind) =
       of nkPragmaExpr: x = x[0]
       of nkIdent: break
       else: illFormedAst(x)
-    c.toInject.incl(x.ident.id)
+    let ident = getIdentNode(c, x)
+    if not isTemplParam(c, ident):
+      c.toInject.incl(x.ident.id)
+    else:
+      replaceIdentBySym(n, ident)
   else:
     let ident = getIdentNode(c, n)
     if not isTemplParam(c, ident):
@@ -171,7 +175,7 @@ proc semTemplSymbol(c: PContext, n: PNode, s: PSym): PNode =
   of skUnknown: 
     # Introduced in this pass! Leave it as an identifier.
     result = n
-  of skProc, skMethod, skIterator, skConverter, skTemplate, skMacro:
+  of OverloadableSyms:
     result = symChoice(c, n, s, scOpen)
   of skGenericParam: 
     result = newSymNodeTypeDesc(s, n.info)
@@ -228,6 +232,18 @@ proc semTemplSomeDecl(c: var TemplCtx, n: PNode, symKind: TSymKind) =
     for j in countup(0, L-3):
       addLocalDecl(c, a.sons[j], symKind)
 
+proc onlyReplaceParams(c: var TemplCtx, n: PNode): PNode =
+  result = n
+  if n.kind == nkIdent:
+    let s = qualifiedLookUp(c.c, n, {})
+    if s != nil:
+      if s.owner == c.owner and s.kind == skParam:
+        incl(s.flags, sfUsed)
+        result = newSymNode(s, n.info)
+  else:
+    for i in 0 .. <n.safeLen:
+      result.sons[i] = onlyReplaceParams(c, n.sons[i])
+
 proc semPattern(c: PContext, n: PNode): PNode
 proc semTemplBody(c: var TemplCtx, n: PNode): PNode = 
   result = n
@@ -348,7 +364,9 @@ proc semTemplBody(c: var TemplCtx, n: PNode): PNode =
   of nkMethodDef:
     result = semRoutineInTemplBody(c, n, skMethod)
   of nkIteratorDef:
-    result = semRoutineInTemplBody(c, n, skIterator)
+    let kind = if hasPragma(n[pragmasPos], wClosure): skClosureIterator
+               else: skIterator
+    result = semRoutineInTemplBody(c, n, kind)
   of nkTemplateDef:
     result = semRoutineInTemplBody(c, n, skTemplate)
   of nkMacroDef:
@@ -357,8 +375,10 @@ proc semTemplBody(c: var TemplCtx, n: PNode): PNode =
     result = semRoutineInTemplBody(c, n, skConverter)
   of nkPragmaExpr:
     result.sons[0] = semTemplBody(c, n.sons[0])
+  of nkPostfix:
+    result.sons[1] = semTemplBody(c, n.sons[1])
   of nkPragma:
-    discard
+    result = onlyReplaceParams(c, n)
   else:
     # dotExpr is ambiguous: note that we explicitely allow 'x.TemplateParam',
     # so we use the generic code for nkDotExpr too
diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index 44e414e9c..c53dc0f7d 100644
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -139,34 +139,45 @@ proc semVarType(c: PContext, n: PNode, prev: PType): PType =
     addSonSkipIntLit(result, base)
   else:
     result = newConstraint(c, tyVar)
-  
+
 proc semDistinct(c: PContext, n: PNode, prev: PType): PType = 
-  if sonsLen(n) == 1:
-    result = newOrPrevType(tyDistinct, prev, c)
-    addSonSkipIntLit(result, semTypeNode(c, n.sons[0], nil))
-  else:
-    result = newConstraint(c, tyDistinct)
+  if n.len == 0: return newConstraint(c, tyDistinct)
+  result = newOrPrevType(tyDistinct, prev, c)
+  addSonSkipIntLit(result, semTypeNode(c, n.sons[0], nil))
+  if n.len > 1: result.n = n[1]
   
-proc semRangeAux(c: PContext, n: PNode, prev: PType): PType = 
+proc semRangeAux(c: PContext, n: PNode, prev: PType): PType =
   assert isRange(n)
   checkSonsLen(n, 3)
   result = newOrPrevType(tyRange, prev, c)
   result.n = newNodeI(nkRange, n.info)
-  if (n[1].kind == nkEmpty) or (n[2].kind == nkEmpty): 
+  if (n[1].kind == nkEmpty) or (n[2].kind == nkEmpty):
     localError(n.info, errRangeIsEmpty)
-  var a = semConstExpr(c, n[1])
-  var b = semConstExpr(c, n[2])
-  if not sameType(a.typ, b.typ):
+  
+  var range: array[2, PNode]
+  range[0] = semExprWithType(c, n[1], {efDetermineType})
+  range[1] = semExprWithType(c, n[2], {efDetermineType})
+  
+  var rangeT: array[2, PType]
+  for i in 0..1: rangeT[i] = range[i].typ.skipTypes({tyStatic}).skipIntLit
+
+  if not sameType(rangeT[0], rangeT[1]):
     localError(n.info, errPureTypeMismatch)
-  elif a.typ.kind notin {tyInt..tyInt64,tyEnum,tyBool,tyChar,
-                         tyFloat..tyFloat128,tyUInt8..tyUInt32}:
+  elif not rangeT[0].isOrdinalType:
     localError(n.info, errOrdinalTypeExpected)
-  elif enumHasHoles(a.typ): 
-    localError(n.info, errEnumXHasHoles, a.typ.sym.name.s)
-  elif not leValue(a, b): localError(n.info, errRangeIsEmpty)
-  addSon(result.n, a)
-  addSon(result.n, b)
-  addSonSkipIntLit(result, b.typ)
+  elif enumHasHoles(rangeT[0]):
+    localError(n.info, errEnumXHasHoles, rangeT[0].sym.name.s)
+  
+  for i in 0..1:
+    if hasGenericArguments(range[i]):
+      result.n.addSon makeStaticExpr(c, range[i])
+    else:
+      result.n.addSon semConstExpr(c, range[i])
+ 
+  if weakLeValue(result.n[0], result.n[1]) == impNo:
+    localError(n.info, errRangeIsEmpty)
+
+  addSonSkipIntLit(result, rangeT[0])
 
 proc semRange(c: PContext, n: PNode, prev: PType): PType =
   result = nil
@@ -186,11 +197,6 @@ proc semRange(c: PContext, n: PNode, prev: PType): PType =
     localError(n.info, errXExpectsOneTypeParam, "range")
     result = newOrPrevType(tyError, prev, c)
 
-proc nMinusOne(n: PNode): PNode =
-  result = newNode(nkCall, n.info, @[
-    newSymNode(getSysMagic("<", mUnaryLt)),
-    n])
-
 proc semArray(c: PContext, n: PNode, prev: PType): PType = 
   var indx, base: PType
   result = newOrPrevType(tyArray, prev, c)
@@ -200,7 +206,7 @@ proc semArray(c: PContext, n: PNode, prev: PType): PType =
     else:
       let e = semExprWithType(c, n.sons[1], {efDetermineType})
       if e.typ.kind == tyFromExpr:
-        indx = e.typ
+        indx = makeRangeWithStaticExpr(c, e.typ.n)
       elif e.kind in {nkIntLit..nkUInt64Lit}:
         indx = makeRangeType(c, 0, e.intVal-1, n.info, e.typ)
       elif e.kind == nkSym and e.typ.kind == tyStatic:
@@ -208,7 +214,8 @@ proc semArray(c: PContext, n: PNode, prev: PType): PType =
         internalAssert c.inGenericContext > 0
         if not isOrdinalType(e.typ.lastSon):
           localError(n[1].info, errOrdinalTypeExpected)
-        indx = e.typ
+        indx = makeRangeWithStaticExpr(c, e)
+        indx.flags.incl tfUnresolved
       elif e.kind in nkCallKinds and hasGenericArguments(e):
         if not isOrdinalType(e.typ):
           localError(n[1].info, errOrdinalTypeExpected)
@@ -217,12 +224,7 @@ proc semArray(c: PContext, n: PNode, prev: PType): PType =
         # We are going to construct a range type that will be
         # properly filled-out in semtypinst (see how tyStaticExpr
         # is handled there).
-        let intType = getSysType(tyInt)
-        indx = newTypeS(tyRange, c)
-        indx.sons = @[intType]
-        indx.n = newNode(nkRange, n.info, @[
-          newIntTypeNode(nkIntLit, 0, intType),
-          makeStaticExpr(c, e.nMinusOne)])
+        indx = makeRangeWithStaticExpr(c, e)
       else:
         indx = e.typ.skipTypes({tyTypeDesc})
     addSonSkipIntLit(result, indx)
@@ -271,6 +273,18 @@ proc semTypeIdent(c: PContext, n: PNode): PSym =
         result = result.typ.sym.copySym
         result.typ = copyType(result.typ, result.typ.owner, true)
         result.typ.flags.incl tfUnresolved
+      
+      if result.kind == skGenericParam:
+        if result.typ.kind == tyGenericParam and result.typ.len == 0 and
+           tfWildcard in result.typ.flags:
+          # collapse the wild-card param to a type
+          result.kind = skType
+          result.typ.flags.excl tfWildcard
+          return
+        else:
+          localError(n.info, errTypeExpected)
+          return errorSym(c, n)
+
       if result.kind != skType: 
         # this implements the wanted ``var v: V, x: V`` feature ...
         var ov: TOverloadIter
@@ -601,16 +615,36 @@ proc semObjectNode(c: PContext, n: PNode, prev: PType): PType =
   if base == nil and tfInheritable notin result.flags:
     incl(result.flags, tfFinal)
 
+proc findEnforcedStaticType(t: PType): PType =
+  # This handles types such as `static[T] and Foo`,
+  # which are subset of `static[T]`, hence they could
+  # be treated in the same way
+  if t.kind == tyStatic: return t
+  if t.kind == tyAnd:
+    for s in t.sons:
+      let t = findEnforcedStaticType(s)
+      if t != nil: return t
+
 proc addParamOrResult(c: PContext, param: PSym, kind: TSymKind) =
-  if kind == skMacro and param.typ.kind notin {tyTypeDesc, tyStatic}:
-    # within a macro, every param has the type PNimrodNode!
-    # and param.typ.kind in {tyTypeDesc, tyExpr, tyStmt}:
-    let nn = getSysSym"PNimrodNode"
-    var a = copySym(param)
-    a.typ = nn.typ
-    if sfGenSym notin a.flags: addDecl(c, a)
+  template addDecl(x) =
+    if sfGenSym notin x.flags: addDecl(c, x)
+
+  if kind == skMacro:
+    let staticType = findEnforcedStaticType(param.typ)
+    if staticType != nil:
+      var a = copySym(param)
+      a.typ = staticType.base
+      addDecl(a)
+    elif param.typ.kind == tyTypeDesc:
+      addDecl(param)
+    else:
+      # within a macro, every param has the type PNimrodNode!
+      let nn = getSysSym"PNimrodNode"
+      var a = copySym(param)
+      a.typ = nn.typ
+      addDecl(a)
   else:
-    if sfGenSym notin param.flags: addDecl(c, param)
+    addDecl(param)
 
 let typedescId = getIdent"typedesc"
 
@@ -644,6 +678,7 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
     s.position = genericParams.len
     genericParams.addSon(newSymNode(s))
     result = typeClass
+    addDecl(c, s)
  
   # XXX: There are codegen errors if this is turned into a nested proc
   template liftingWalk(typ: PType, anonFlag = false): expr =
@@ -653,6 +688,10 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
   var paramTypId = if not anon and paramType.sym != nil: paramType.sym.name
                    else: nil
 
+  template maybeLift(typ: PType): expr =
+    let lifted = liftingWalk(typ)
+    (if lifted != nil: lifted else: typ)
+
   template addImplicitGeneric(e: expr): expr =
     addImplicitGenericImpl(e, paramTypId)
 
@@ -663,15 +702,21 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
   of tyStatic:
     # proc(a: expr{string}, b: expr{nkLambda})
     # overload on compile time values and AST trees
-    result = addImplicitGeneric(c.newTypeWithSons(tyStatic, paramType.sons))
-    result.flags.incl tfHasStatic
+    if paramType.n != nil: return # this is a concrete type
+    if tfUnresolved in paramType.flags: return # already lifted
+    let base = paramType.base.maybeLift
+    if base.isMetaType and procKind == skMacro:
+      localError(info, errMacroBodyDependsOnGenericTypes, paramName)
+    result = addImplicitGeneric(c.newTypeWithSons(tyStatic, @[base]))
+    result.flags.incl({tfHasStatic, tfUnresolved})
   
   of tyTypeDesc:
     if tfUnresolved notin paramType.flags:
       # naked typedescs are not bindOnce types
-      if paramType.sonsLen == 0 and paramTypId != nil and
+      if paramType.base.kind == tyNone and paramTypId != nil and
          paramTypId.id == typedescId.id: paramTypId = nil
-      result = addImplicitGeneric(c.newTypeWithSons(tyTypeDesc, paramType.sons))
+      result = addImplicitGeneric(
+        c.newTypeWithSons(tyTypeDesc, @[paramType.base]))
   
   of tyDistinct:
     if paramType.sonsLen == 1:
@@ -703,12 +748,26 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
     for i in 0 .. paramType.sonsLen - 2:
       result.rawAddSon newTypeS(tyAnything, c)
       # result.rawAddSon(copyType(paramType.sons[i], getCurrOwner(), true))
+
+    if paramType.lastSon.kind == tyUserTypeClass:
+      result.kind = tyUserTypeClassInst
+      result.rawAddSon paramType.lastSon
+      return addImplicitGeneric(result)
+   
     result = instGenericContainer(c, paramType.sym.info, result,
                                   allowMetaTypes = true)
-    result.lastSon.shouldHaveMeta
     result = newTypeWithSons(c, tyCompositeTypeClass, @[paramType, result])
     result = addImplicitGeneric(result)
-  
+
+  of tyIter:
+    if paramType.callConv == ccInline:
+      if procKind notin {skTemplate, skMacro, skIterator}:
+        localError(info, errInlineIteratorsAsProcParams)
+      if paramType.len == 1:
+        let lifted = liftingWalk(paramType.base)
+        if lifted != nil: paramType.sons[0] = lifted
+      result = addImplicitGeneric(paramType)
+
   of tyGenericInst:
     if paramType.lastSon.kind == tyUserTypeClass:
       var cp = copyType(paramType, getCurrOwner(), false)
@@ -722,7 +781,7 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
         result = paramType
         result.lastSon.shouldHaveMeta
 
-    let liftBody = liftingWalk(paramType.lastSon)
+    let liftBody = liftingWalk(paramType.lastSon, true)
     if liftBody != nil:
       result = liftBody
       result.shouldHaveMeta
@@ -734,7 +793,7 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
 
     let expanded = instGenericContainer(c, info, paramType,
                                         allowMetaTypes = true)
-    result = liftingWalk(expanded)
+    result = liftingWalk(expanded, true)
 
   of tyUserTypeClass, tyBuiltInTypeClass, tyAnd, tyOr, tyNot:
     result = addImplicitGeneric(copyType(paramType, getCurrOwner(), true))
@@ -744,12 +803,11 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
       result = addImplicitGeneric(newTypeS(tyAnything, c))
   
   of tyGenericParam:
-    if tfGenericTypeParam in paramType.flags and false:
-      if paramType.sonsLen > 0:
-        result = liftingWalk(paramType.lastSon)
-      else:
-        result = addImplicitGeneric(newTypeS(tyAnything, c))
- 
+    markUsed(genericParams, paramType.sym)
+    if tfWildcard in paramType.flags:
+      paramType.flags.excl tfWildcard
+      paramType.sym.kind = skType
+    
   else: discard
 
   # result = liftingWalk(paramType)
@@ -761,8 +819,8 @@ proc semParamType(c: PContext, n: PNode, constraint: var PNode): PType =
   else:
     result = semTypeNode(c, n, nil)
 
-proc semProcTypeNode(c: PContext, n, genericParams: PNode, 
-                     prev: PType, kind: TSymKind): PType = 
+proc semProcTypeNode(c: PContext, n, genericParams: PNode,
+                     prev: PType, kind: TSymKind): PType =
   var
     res: PNode
     cl: TIntSet
@@ -827,9 +885,13 @@ proc semProcTypeNode(c: PContext, n, genericParams: PNode,
       addParamOrResult(c, arg, kind)
       if gCmd == cmdPretty: checkDef(a.sons[j], arg)
 
-
+  var r: PType
   if n.sons[0].kind != nkEmpty:
-    var r = semTypeNode(c, n.sons[0], nil)
+    r = semTypeNode(c, n.sons[0], nil)
+  elif kind == skIterator:
+    r = newTypeS(tyAnything, c)
+  
+  if r != nil:
     # turn explicit 'void' return type into 'nil' because the rest of the 
     # compiler only checks for 'nil':
     if skipTypes(r, {tyGenericInst}).kind != tyEmpty:
@@ -838,8 +900,20 @@ proc semProcTypeNode(c: PContext, n, genericParams: PNode,
                                    n.sons[0].info)
         if lifted != nil: r = lifted
         r.flags.incl tfRetType
-      result.sons[0] = skipIntLit(r)
-      res.typ = result.sons[0]
+      r = skipIntLit(r)
+      if kind == skIterator:
+        # see tchainediterators
+        # in cases like iterator foo(it: iterator): type(it)
+        # we don't need to change the return type to iter[T]
+        if not r.isInlineIterator: r = newTypeWithSons(c, tyIter, @[r])
+      result.sons[0] = r
+      res.typ = r
+
+  if genericParams != nil:
+    for n in genericParams:
+      if tfWildcard in n.sym.typ.flags:
+        n.sym.kind = skType
+        n.sym.typ.flags.excl tfWildcard
 
 proc semStmtListType(c: PContext, n: PNode, prev: PType): PType =
   checkMinSonsLen(n, 1)
@@ -868,9 +942,18 @@ proc semBlockType(c: PContext, n: PNode, prev: PType): PType =
 proc semGenericParamInInvokation(c: PContext, n: PNode): PType =
   result = semTypeNode(c, n, nil)
 
-proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType = 
+proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
+  if s.typ == nil:
+    localError(n.info, "cannot instantiate the '$1' $2" %
+                       [s.name.s, ($s.kind).substr(2).toLower])
+    return newOrPrevType(tyError, prev, c)
+  
+  var t = s.typ
+  if t.kind == tyCompositeTypeClass and t.base.kind == tyGenericBody:
+    t = t.base
+
   result = newOrPrevType(tyGenericInvokation, prev, c)
-  addSonSkipIntLit(result, s.typ)
+  addSonSkipIntLit(result, t)
 
   template addToResult(typ) =
     if typ.isNil:
@@ -878,27 +961,24 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
       rawAddSon(result, typ)
     else: addSonSkipIntLit(result, typ)
 
-  if s.typ == nil:
-    localError(n.info, errCannotInstantiateX, s.name.s)
-    return newOrPrevType(tyError, prev, c)
-  elif s.typ.kind == tyForward:
+  if t.kind == tyForward:
     for i in countup(1, sonsLen(n)-1):
       var elem = semGenericParamInInvokation(c, n.sons[i])
       addToResult(elem)
-  elif s.typ.kind != tyGenericBody:
+    return
+  elif t.kind != tyGenericBody:
     #we likely got code of the form TypeA[TypeB] where TypeA is
     #not generic.
     localError(n.info, errNoGenericParamsAllowedForX, s.name.s)
     return newOrPrevType(tyError, prev, c)
   else:
-
-    var m = newCandidate(c, s, n)
+    var m = newCandidate(c, t)
     matches(c, n, copyTree(n), m)
     
     if m.state != csMatch:
-      var err = "cannot instantiate " & typeToString(s.typ) & "\n" &
+      var err = "cannot instantiate " & typeToString(t) & "\n" &
                 "got: (" & describeArgs(c, n) & ")\n" &
-                "but expected: (" & describeArgs(c, s.typ.n, 0) & ")"
+                "but expected: (" & describeArgs(c, t.n, 0) & ")"
       localError(n.info, errGenerated, err)
       return newOrPrevType(tyError, prev, c)
 
@@ -908,9 +988,10 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
       let typ = m.call[i].typ.skipTypes({tyTypeDesc})
       if containsGenericType(typ): isConcrete = false
       addToResult(typ)
-    
+   
     if isConcrete:
-      if s.ast == nil:
+      if s.ast == nil and s.typ.kind != tyCompositeTypeClass:
+        # XXX: What kind of error is this? is it still relevant?
         localError(n.info, errCannotInstantiateX, s.name.s)
         result = newOrPrevType(tyError, prev, c)
       else:
@@ -944,6 +1025,23 @@ proc semTypeClass(c: PContext, n: PNode, prev: PType): PType =
       let typ = semTypeNode(c, n, nil)
       result.sons.safeAdd(typ)
 
+proc semProcTypeWithScope(c: PContext, n: PNode,
+                        prev: PType, kind: TSymKind): PType =
+  checkSonsLen(n, 2)
+  openScope(c)
+  result = semProcTypeNode(c, n.sons[0], nil, prev, kind)
+  # dummy symbol for `pragma`:
+  var s = newSymS(kind, newIdentNode(getIdent("dummy"), n.info), c)
+  s.typ = result
+  if n.sons[1].kind == nkEmpty or n.sons[1].len == 0:
+    if result.callConv == ccDefault:
+      result.callConv = ccClosure
+      #Message(n.info, warnImplicitClosure, renderTree(n))
+  else:
+    pragma(c, s, n.sons[1], procTypePragmas)
+    when useEffectSystem: setEffectsForProcType(result, n.sons[1])
+  closeScope(c)
+
 proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
   result = nil
   if gCmd == cmdIdeTools: suggestExpr(c, n)
@@ -952,7 +1050,8 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
   of nkTypeOfExpr:
     # for ``type(countup(1,3))``, see ``tests/ttoseq``.
     checkSonsLen(n, 1)
-    result = semExprWithType(c, n.sons[0], {efInTypeof}).typ
+    let typExpr = semExprWithType(c, n.sons[0], {efInTypeof})
+    result = typExpr.typ.skipTypes({tyIter})
   of nkPar: 
     if sonsLen(n) == 1: result = semTypeNode(c, n.sons[0], prev)
     else:
@@ -1011,28 +1110,32 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
     of mOrdinal: result = semOrdinal(c, n, prev)
     of mSeq: result = semContainer(c, n, tySequence, "seq", prev)
     of mVarargs: result = semVarargs(c, n, prev)
-    of mExpr, mTypeDesc:
+    of mTypeDesc: result = makeTypeDesc(c, semTypeNode(c, n[1], nil))
+    of mExpr:
       result = semTypeNode(c, n.sons[0], nil)
       if result != nil:
         result = copyType(result, getCurrOwner(), false)
         for i in countup(1, n.len - 1):
           result.rawAddSon(semTypeNode(c, n.sons[i], nil))
     else: result = semGeneric(c, n, s, prev)
-  of nkIdent, nkDotExpr, nkAccQuoted: 
-    if n.kind == nkDotExpr:
-      let head = qualifiedLookUp(c, n[0], {checkAmbiguity, checkUndeclared})
-      if head.kind in {skType}:
-        var toBind = initIntSet()
-        var preprocessed = semGenericStmt(c, n, {}, toBind)
-        return makeTypeFromExpr(c, preprocessed)
+  of nkDotExpr:
+    var typeExpr = semExpr(c, n)
+    if typeExpr.typ.kind != tyTypeDesc:
+      localError(n.info, errTypeExpected)
+      return errorType(c)
+    result = typeExpr.typ.base
+    if result.isMetaType:
+      var toBind = initIntSet()
+      var preprocessed = semGenericStmt(c, n, {}, toBind)
+      return makeTypeFromExpr(c, preprocessed)
+  of nkIdent, nkAccQuoted:
     var s = semTypeIdent(c, n)
     if s.typ == nil: 
       if s.kind != skError: localError(n.info, errTypeExpected)
       result = newOrPrevType(tyError, prev, c)
     elif s.kind == skParam and s.typ.kind == tyTypeDesc:
-      assert s.typ.len > 0
-      internalAssert prev == nil
-      result = s.typ.sons[0]
+      internalAssert s.typ.base.kind != tyNone and prev == nil
+      result = s.typ.base
     elif prev == nil:
       result = s.typ
     else: 
@@ -1066,27 +1169,22 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
     var base = semTypeNode(c, n.sons[0], nil)
     result.rawAddSon(base)
     result.flags.incl tfHasStatic
-  of nkProcTy, nkIteratorTy:
+  of nkIteratorTy:
     if n.sonsLen == 0:
-      result = newConstraint(c, tyProc)
+      result = newConstraint(c, tyIter)
     else:
-      checkSonsLen(n, 2)
-      openScope(c)
-      result = semProcTypeNode(c, n.sons[0], nil, prev, skProc)
-      # dummy symbol for `pragma`:
-      var s = newSymS(skProc, newIdentNode(getIdent("dummy"), n.info), c)
-      s.typ = result
-      if n.sons[1].kind == nkEmpty or n.sons[1].len == 0:
-        if result.callConv == ccDefault:
-          result.callConv = ccClosure
-          #Message(n.info, warnImplicitClosure, renderTree(n))
+      result = semProcTypeWithScope(c, n, prev, skClosureIterator)
+      if n.lastSon.kind == nkPragma and hasPragma(n.lastSon, wInline):
+        result.kind = tyIter
+        result.callConv = ccInline
       else:
-        pragma(c, s, n.sons[1], procTypePragmas)
-        when useEffectSystem: setEffectsForProcType(result, n.sons[1])
-      closeScope(c)
-    if n.kind == nkIteratorTy:
-      result.flags.incl(tfIterator)
-      result.callConv = ccClosure
+        result.flags.incl(tfIterator)
+        result.callConv = ccClosure
+  of nkProcTy:
+    if n.sonsLen == 0:
+      result = newConstraint(c, tyProc)
+    else:
+      result = semProcTypeWithScope(c, n, prev, skProc)
   of nkEnumTy: result = semEnum(c, n, prev)
   of nkType: result = n.typ
   of nkStmtListType: result = semStmtListType(c, n, prev)
@@ -1196,6 +1294,7 @@ proc semGenericParamList(c: PContext, n: PNode, father: PType = nil): PNode =
     
     if typ == nil:
       typ = newTypeS(tyGenericParam, c)
+      if father == nil: typ.flags.incl tfWildcard
 
     typ.flags.incl tfGenericTypeParam
 
@@ -1206,8 +1305,7 @@ proc semGenericParamList(c: PContext, n: PNode, father: PType = nil): PNode =
                       # type for each generic param. the index
                       # of the parameter will be stored in the
                       # attached symbol.
-      var s = case finalType.kind
-        of tyStatic:
+      var s = if finalType.kind == tyStatic or tfWildcard in typ.flags:
           newSymG(skGenericParam, a.sons[j], c).linkTo(finalType)
         else:
           newSymG(skType, a.sons[j], c).linkTo(finalType)
diff --git a/compiler/semtypinst.nim b/compiler/semtypinst.nim
index a07d91241..4a8a463f5 100644
--- a/compiler/semtypinst.nim
+++ b/compiler/semtypinst.nim
@@ -29,6 +29,7 @@ proc checkConstructedType*(info: TLineInfo, typ: PType) =
     localError(info, errVarVarTypeNotAllowed)
   elif computeSize(t) == szIllegalRecursion:
     localError(info, errIllegalRecursionInTypeX, typeToString(t))
+  
   when false:
     if t.kind == tyObject and t.sons[0] != nil:
       if t.sons[0].kind != tyObject or tfFinal in t.sons[0].flags: 
@@ -79,7 +80,7 @@ type
 
 proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType
 proc replaceTypeVarsS(cl: var TReplTypeVars, s: PSym): PSym
-proc replaceTypeVarsN(cl: var TReplTypeVars, n: PNode): PNode
+proc replaceTypeVarsN*(cl: var TReplTypeVars, n: PNode): PNode
 
 template checkMetaInvariants(cl: TReplTypeVars, t: PType) =
   when false:
@@ -95,8 +96,11 @@ proc replaceTypeVarsT*(cl: var TReplTypeVars, t: PType): PType =
   checkMetaInvariants(cl, result)
 
 proc prepareNode(cl: var TReplTypeVars, n: PNode): PNode =
+  let t = replaceTypeVarsT(cl, n.typ)
+  if t != nil and t.kind == tyStatic and t.n != nil:
+    return t.n
   result = copyNode(n)
-  result.typ = replaceTypeVarsT(cl, n.typ)
+  result.typ = t
   if result.kind == nkSym: result.sym = replaceTypeVarsS(cl, n.sym)
   let isCall = result.kind in nkCallKinds
   for i in 0 .. <n.safeLen:
@@ -153,6 +157,9 @@ proc replaceTypeVarsN(cl: var TReplTypeVars, n: PNode): PNode =
     discard
   of nkSym:
     result.sym = replaceTypeVarsS(cl, n.sym)
+    if result.sym.typ.kind == tyEmpty:
+      # don't add the 'void' field
+      result = newNode(nkRecList, n.info)
   of nkRecWhen:
     var branch: PNode = nil              # the branch to take
     for i in countup(0, sonsLen(n) - 1):
@@ -177,7 +184,8 @@ proc replaceTypeVarsN(cl: var TReplTypeVars, n: PNode): PNode =
   of nkStaticExpr:
     var n = prepareNode(cl, n)
     n = reResolveCallsWithTypedescParams(cl, n)
-    result = cl.c.semExpr(cl.c, n)
+    result = if cl.allowMetaTypes: n
+             else: cl.c.semExpr(cl.c, n)
   else:
     var length = sonsLen(n)
     if length > 0:
@@ -192,10 +200,10 @@ proc replaceTypeVarsS(cl: var TReplTypeVars, s: PSym): PSym =
     result = copySym(s, false)
     incl(result.flags, sfFromGeneric)
     idTablePut(cl.symMap, s, result)
-    result.typ = replaceTypeVarsT(cl, s.typ)
     result.owner = s.owner
+    result.typ = replaceTypeVarsT(cl, s.typ)
     result.ast = replaceTypeVarsN(cl, s.ast)
-
+    
 proc lookupTypeVar(cl: TReplTypeVars, t: PType): PType = 
   result = PType(idTableGet(cl.typeMap, t))
   if result == nil:
@@ -205,7 +213,7 @@ proc lookupTypeVar(cl: TReplTypeVars, t: PType): PType =
   elif result.kind == tyGenericParam and not cl.allowMetaTypes:
     internalError(cl.info, "substitution with generic parameter")
 
-proc instCopyType(cl: var TReplTypeVars, t: PType): PType =
+proc instCopyType*(cl: var TReplTypeVars, t: PType): PType =
   # XXX: relying on allowMetaTypes is a kludge
   result = copyType(t, t.owner, cl.allowMetaTypes)
   result.flags.incl tfFromGeneric
@@ -216,7 +224,7 @@ proc handleGenericInvokation(cl: var TReplTypeVars, t: PType): PType =
   # is difficult to handle: 
   var body = t.sons[0]
   if body.kind != tyGenericBody: internalError(cl.info, "no generic body")
-  var header: PType = nil
+  var header: PType = t
   # search for some instantiation here:
   if cl.allowMetaTypes:
     result = PType(idTableGet(cl.localCache, t))
@@ -228,11 +236,13 @@ proc handleGenericInvokation(cl: var TReplTypeVars, t: PType): PType =
     if x.kind == tyGenericParam:
       x = lookupTypeVar(cl, x)
       if x != nil:
-        if header == nil: header = instCopyType(cl, t)
+        if header == t: header = instCopyType(cl, t)
         header.sons[i] = x
         propagateToOwner(header, x)
+    else:
+      propagateToOwner(header, x)
   
-  if header != nil:
+  if header != t:
     # search again after first pass:
     result = searchInstTypes(header)
     if result != nil: return
@@ -240,6 +250,7 @@ proc handleGenericInvokation(cl: var TReplTypeVars, t: PType): PType =
     header = instCopyType(cl, t)
   
   result = newType(tyGenericInst, t.sons[0].owner)
+  result.flags = header.flags
   # be careful not to propagate unnecessary flags here (don't use rawAddSon)
   result.sons = @[header.sons[0]]
   # ugh need another pass for deeply recursive generic types (e.g. PActor)
@@ -273,7 +284,7 @@ proc handleGenericInvokation(cl: var TReplTypeVars, t: PType): PType =
   rawAddSon(result, newbody)
   checkPartialConstructedType(cl.info, newbody)
 
-proc eraseVoidParams(t: PType) =
+proc eraseVoidParams*(t: PType) =
   if t.sons[0] != nil and t.sons[0].kind == tyEmpty:
     t.sons[0] = nil
   
@@ -290,7 +301,7 @@ proc eraseVoidParams(t: PType) =
       setLen t.n.sons, pos
       return
 
-proc skipIntLiteralParams(t: PType) =
+proc skipIntLiteralParams*(t: PType) =
   for i in 0 .. <t.sonsLen:
     let p = t.sons[i]
     if p == nil: continue
@@ -298,6 +309,11 @@ proc skipIntLiteralParams(t: PType) =
     if skipped != p:
       t.sons[i] = skipped
       if i > 0: t.n.sons[i].sym.typ = skipped
+  
+  # when the typeof operator is used on a static input
+  # param, the results gets infected with static as well:
+  if t.sons[0] != nil and t.sons[0].kind == tyStatic:
+    t.sons[0] = t.sons[0].base
 
 proc propagateFieldFlags(t: PType, n: PNode) =
   # This is meant for objects and tuples
@@ -307,16 +323,15 @@ proc propagateFieldFlags(t: PType, n: PNode) =
   of nkSym:
     propagateToOwner(t, n.sym.typ)
   of nkRecList, nkRecCase, nkOfBranch, nkElse:
-    if n.sons != nil:
-      for son in n.sons:
-        propagateFieldFlags(t, son)
+    for son in n:
+      propagateFieldFlags(t, son)
   else: discard
 
 proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
   result = t
   if t == nil: return
 
-  if t.kind in {tyStatic, tyGenericParam} + tyTypeClasses:
+  if t.kind in {tyStatic, tyGenericParam, tyIter} + tyTypeClasses:
     let lookup = PType(idTableGet(cl.typeMap, t))
     if lookup != nil: return lookup
   
@@ -329,6 +344,7 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
     result = replaceTypeVarsT(cl, lastSon(t))
 
   of tyFromExpr:
+    if cl.allowMetaTypes: return
     var n = prepareNode(cl, t.n)
     n = cl.c.semConstExpr(cl.c, n)
     if n.typ.kind == tyTypeDesc:
@@ -381,21 +397,11 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
           propagateToOwner(result, result.sons[i])
 
       result.n = replaceTypeVarsN(cl, result.n)
-      
-      # XXX: This is not really needed?
-      # if result.kind in GenericTypes:
-      #   localError(cl.info, errCannotInstantiateX, typeToString(t, preferName))
-
+     
       case result.kind
       of tyArray:
         let idx = result.sons[0]
-        if idx.kind == tyStatic:
-          if idx.n == nil:
-            let lookup = lookupTypeVar(cl, idx)
-            internalAssert lookup != nil
-            idx.n = lookup.n
-
-          result.sons[0] = makeRangeType(cl.c, 0, idx.n.intVal - 1, idx.n.info)
+        internalAssert idx.kind != tyStatic
        
       of tyObject, tyTuple:
         propagateFieldFlags(result, result.n)
@@ -406,14 +412,22 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
       
       else: discard
 
+proc initTypeVars*(p: PContext, pt: TIdTable, info: TLineInfo): TReplTypeVars =
+  initIdTable(result.symMap)
+  copyIdTable(result.typeMap, pt)
+  initIdTable(result.localCache)
+  result.info = info
+  result.c = p
+
+proc replaceTypesInBody*(p: PContext, pt: TIdTable, n: PNode): PNode =
+  var cl = initTypeVars(p, pt, n.info)
+  pushInfoContext(n.info)
+  result = replaceTypeVarsN(cl, n)
+  popInfoContext()
+  
 proc generateTypeInstance*(p: PContext, pt: TIdTable, info: TLineInfo,
                            t: PType): PType =
-  var cl: TReplTypeVars
-  initIdTable(cl.symMap)
-  copyIdTable(cl.typeMap, pt)
-  initIdTable(cl.localCache)
-  cl.info = info
-  cl.c = p
+  var cl = initTypeVars(p, pt, info)
   pushInfoContext(info)
   result = replaceTypeVarsT(cl, t)
   popInfoContext()
diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim
index 335ceafeb..b9fb0c957 100644
--- a/compiler/sigmatch.nim
+++ b/compiler/sigmatch.nim
@@ -12,7 +12,7 @@
 
 import 
   intsets, ast, astalgo, semdata, types, msgs, renderer, lookups, semtypinst,
-  magicsys, condsyms, idents, lexer, options, parampatterns, strutils
+  magicsys, condsyms, idents, lexer, options, parampatterns, strutils, trees
 
 when not defined(noDocgen):
   import docgen
@@ -40,6 +40,8 @@ type
     proxyMatch*: bool        # to prevent instantiations
     genericConverter*: bool  # true if a generic converter needs to
                              # be instantiated
+    coerceDistincts*: bool   # this is an explicit coercion that can strip away
+                             # a distrinct type
     typedescMatched: bool
     inheritancePenalty: int  # to prefer closest father object type
     errors*: seq[string]     # additional clarifications to be displayed to the
@@ -51,6 +53,8 @@ type
     isSubtype,
     isSubrange,              # subrange of the wanted type; no type conversion
                              # but apart from that counts as ``isSubtype``
+    isInferred,              # generic proc was matched against a concrete type
+    isInferredConvertible,   # same as above, but requiring proc CC conversion
     isGeneric,
     isFromIntLit,            # conversion *from* int literal; proven safe
     isEqual
@@ -112,6 +116,9 @@ proc newCandidate*(ctx: PContext, callee: PSym,
                    binding: PNode, calleeScope = -1): TCandidate =
   initCandidate(ctx, result, callee, binding, calleeScope)
 
+proc newCandidate*(ctx: PContext, callee: PType): TCandidate =
+  initCandidate(ctx, result, callee)
+
 proc copyCandidate(a: var TCandidate, b: TCandidate) = 
   a.c = b.c
   a.exactMatches = b.exactMatches
@@ -338,34 +345,60 @@ proc recordRel(c: var TCandidate, f, a: PType): TTypeRelation =
 proc allowsNil(f: PType): TTypeRelation {.inline.} =
   result = if tfNotNil notin f.flags: isSubtype else: isNone
 
-proc procTypeRel(c: var TCandidate, f, a: PType): TTypeRelation =
-  proc inconsistentVarTypes(f, a: PType): bool {.inline.} =
-    result = f.kind != a.kind and (f.kind == tyVar or a.kind == tyVar)
+proc inconsistentVarTypes(f, a: PType): bool {.inline.} =
+  result = f.kind != a.kind and (f.kind == tyVar or a.kind == tyVar)
+
+proc procParamTypeRel(c: var TCandidate, f, a: PType): TTypeRelation =
+  var f = f
+
+  if a.isMetaType:
+    if f.isMetaType:
+      # We are matching a generic proc (as proc param)
+      # to another generic type appearing in the proc
+      # signature. There is a change that the target
+      # type is already fully-determined, so we are 
+      # going to try resolve it
+      f = generateTypeInstance(c.c, c.bindings, c.call.info, f)
+      if f == nil or f.isMetaType:
+        # no luck resolving the type, so the inference fails
+        return isNone
+    let reverseRel = typeRel(c, a, f)
+    if reverseRel == isGeneric:
+      result = isInferred
+      inc c.genericMatches
+  else:
+    result = typeRel(c, f, a)
 
+  if result <= isSubtype or inconsistentVarTypes(f, a):
+    result = isNone
+ 
+  if result == isEqual:
+    inc c.exactMatches
+    
+proc procTypeRel(c: var TCandidate, f, a: PType): TTypeRelation =
   case a.kind
   of tyProc:
     if sonsLen(f) != sonsLen(a): return
-    # Note: We have to do unification for the parameters before the
-    # return type!
     result = isEqual      # start with maximum; also correct for no
                           # params at all
-    for i in countup(1, sonsLen(f)-1):
-      var m = typeRel(c, f.sons[i], a.sons[i])
-      if m <= isSubtype or inconsistentVarTypes(f.sons[i], a.sons[i]):
-        return isNone
-      else: result = minRel(m, result)
+    
+    template checkParam(f, a) =
+      result = minRel(result, procParamTypeRel(c, f, a))
+      if result == isNone: return
+
+    # Note: We have to do unification for the parameters before the
+    # return type!
+    for i in 1 .. <f.sonsLen:
+      checkParam(f.sons[i], a.sons[i])
+    
     if f.sons[0] != nil:
       if a.sons[0] != nil:
-        var m = typeRel(c, f.sons[0], a.sons[0])
-        # Subtype is sufficient for return types!
-        if m < isSubtype or inconsistentVarTypes(f.sons[0], a.sons[0]):
-          return isNone
-        elif m == isSubtype: result = isConvertible
-        else: result = minRel(m, result)
+        checkParam(f.sons[0], a.sons[0])
       else:
         return isNone
     elif a.sons[0] != nil:
       return isNone
+
     if tfNoSideEffect in f.flags and tfNoSideEffect notin a.flags:
       return isNone
     elif tfThread in f.flags and a.flags * {tfThread, tfNoSideEffect} == {}:
@@ -376,12 +409,16 @@ proc procTypeRel(c: var TCandidate, f, a: PType): TTypeRelation =
     elif f.callConv != a.callConv:
       # valid to pass a 'nimcall' thingie to 'closure':
       if f.callConv == ccClosure and a.callConv == ccDefault:
-        result = isConvertible
+        result = if result != isInferred: isConvertible
+                 else: isInferredConvertible
       else:
         return isNone
     when useEffectSystem:
       if not compatibleEffects(f, a): return isNone
-  of tyNil: result = f.allowsNil
+  of tyNil:
+    result = f.allowsNil
+  of tyIter:
+    if tfIterator in f.flags: result = typeRel(c, f.base, a.base)
   else: discard
 
 proc typeRangeRel(f, a: PType): TTypeRelation {.noinline.} =
@@ -402,18 +439,8 @@ proc typeRangeRel(f, a: PType): TTypeRelation {.noinline.} =
 
 proc matchUserTypeClass*(c: PContext, m: var TCandidate,
                          ff, a: PType): TTypeRelation =
-  #if f.n == nil:
-  #  let r = typeRel(m, f, a)
-  #  return if r == isGeneric: arg else: nil
-
   var body = ff.skipTypes({tyUserTypeClassInst})
 
-  # var prev = PType(idTableGet(m.bindings, f))
-  # if prev != nil:
-  #   if sameType(prev, a): return arg
-  #   else: return nil
-
-  # pushInfoContext(arg.info)
   openScope(c)
   inc c.inTypeClass
 
@@ -438,7 +465,8 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate,
     
     if param.kind == nkVarTy:
       dummyName = param[0]
-      dummyType = makeVarType(c, a)
+      dummyType = if a.kind != tyVar: makeVarType(c, a)
+                  else: a
     else:
       dummyName = param
       dummyType = a
@@ -448,7 +476,7 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate,
     dummyParam.typ = dummyType
     addDecl(c, dummyParam)
 
-  var checkedBody = c.semTryExpr(c, copyTree(body.n[3]), bufferErrors = false)
+  var checkedBody = c.semTryExpr(c, body.n[3].copyTree, bufferErrors = false)
   m.errors = bufferedMsgs
   clearBufferedMsgs()
   if checkedBody == nil: return isNone
@@ -462,7 +490,23 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate,
       else: discard
     
   return isGeneric
-  # put(m.bindings, f, a)
+
+proc shouldSkipDistinct(rules: PNode, callIdent: PIdent): bool =
+  if rules.kind == nkWith:
+    for r in rules:
+      if r.considerAcc == callIdent: return true
+    return false
+  else:
+    for r in rules:
+      if r.considerAcc == callIdent: return false
+    return true
+
+proc maybeSkipDistinct(t: PType, callee: PSym): PType =
+  if t != nil and t.kind == tyDistinct and t.n != nil and
+     shouldSkipDistinct(t.n, callee.name):
+    result = t.base
+  else:
+    result = t
 
 proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
   # typeRel can be used to establish various relationships between types:
@@ -491,7 +535,11 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
   assert(aOrig != nil)
 
   # var and static arguments match regular modifier-free types
-  let a = aOrig.skipTypes({tyStatic, tyVar})
+  let a = aOrig.skipTypes({tyStatic, tyVar}).maybeSkipDistinct(c.calleeSym)
+  # XXX: Theoretically, maybeSkipDistinct could be called before we even
+  # start the param matching process. This could be done in `prepareOperand`
+  # for example, but unfortunately `prepareOperand` is not called in certain
+  # situation when nkDotExpr are rotated to nkDotCalls
   
   if a.kind == tyGenericInst and
       skipTypes(f, {tyVar}).kind notin {
@@ -501,8 +549,9 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
 
   template bindingRet(res) =
     when res == isGeneric:
-      let bound = aOrig.skipTypes({tyRange}).skipIntLit
-      put(c.bindings, f, bound)
+      if doBind:
+        let bound = aOrig.skipTypes({tyRange}).skipIntLit
+        if doBind: put(c.bindings, f, bound)
     return res
 
   template considerPreviousT(body: stmt) {.immediate.} =
@@ -599,8 +648,24 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
         else:
           fRange = prev
       result = typeRel(c, f.sons[1], a.sons[1])
-      if result < isGeneric: result = isNone
-      elif lengthOrd(fRange) != lengthOrd(a): result = isNone
+      if result < isGeneric:
+        result = isNone
+      elif tfUnresolved in fRange.flags and
+           rangeHasStaticIf(fRange):
+        # This is a range from an array instantiated with a generic
+        # static param. We must extract the static param here and bind
+        # it to the size of the currently supplied array.
+        var
+          rangeStaticT = fRange.getStaticTypeFromRange
+          replacementT = newTypeWithSons(c.c, tyStatic, @[tyInt.getSysType])
+          inputUpperBound = a.sons[0].n[1].intVal
+        # we must correct for the off-by-one discrepancy between
+        # ranges and static params:
+        replacementT.n = newIntNode(nkIntLit, inputUpperBound + 1)
+        put(c.bindings, rangeStaticT, replacementT)
+        result = isGeneric
+      elif lengthOrd(fRange) != lengthOrd(a):
+        result = isNone
     else: discard
   of tyOpenArray, tyVarargs:
     case a.kind
@@ -662,6 +727,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
           result = isSubtype
   of tyDistinct:
     if (a.kind == tyDistinct) and sameDistinctTypes(f, a): result = isEqual
+    elif c.coerceDistincts: result = typeRel(c, f.base, a)
   of tySet: 
     if a.kind == tySet: 
       if (f.sons[0].kind != tyGenericParam) and (a.sons[0].kind == tyEmpty): 
@@ -824,7 +890,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
 
   of tyUserTypeClass, tyUserTypeClassInst:
     considerPreviousT:
-      result = matchUserTypeClass(c.c, c, f, a)
+      result = matchUserTypeClass(c.c, c, f, aOrig)
       if result == isGeneric:
         put(c.bindings, f, a)
 
@@ -839,20 +905,22 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
   of tyGenericParam:
     var x = PType(idTableGet(c.bindings, f))
     if x == nil:
-      if c.calleeSym != nil and c.calleeSym.kind == skType and
+      if c.callee.kind == tyGenericBody and
          f.kind == tyGenericParam and not c.typedescMatched:
         # XXX: The fact that generic types currently use tyGenericParam for 
         # their parameters is really a misnomer. tyGenericParam means "match
         # any value" and what we need is "match any type", which can be encoded
         # by a tyTypeDesc params. Unfortunately, this requires more substantial
         # changes in semtypinst and elsewhere.
-        if a.kind == tyTypeDesc:
+        if tfWildcard in a.flags:
+          result = isGeneric
+        elif a.kind == tyTypeDesc:
           if f.sonsLen == 0:
             result = isGeneric
           else:
             internalAssert a.sons != nil and a.sons.len > 0
             c.typedescMatched = true
-            result = typeRel(c, f.sons[0], a.sons[0])
+            result = typeRel(c, f.base, a.base)
         else:
           result = isNone
       else:
@@ -862,11 +930,16 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
           result = isGeneric
 
       if result == isGeneric:
-        var concrete = concreteType(c, a)
-        if concrete == nil:
-          result = isNone
+        var concrete = a
+        if tfWildcard in a.flags:
+          a.sym.kind = skType
+          a.flags.excl tfWildcard
         else:
-          if doBind: put(c.bindings, f, concrete)
+          concrete = concreteType(c, a)
+          if concrete == nil:
+            return isNone
+        if doBind:
+          put(c.bindings, f, concrete)
     elif a.kind == tyEmpty:
       result = isGeneric
     elif x.kind == tyGenericParam:
@@ -884,28 +957,57 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
   of tyTypeDesc:
     var prev = PType(idTableGet(c.bindings, f))
     if prev == nil:
-      if a.kind == tyTypeDesc:
-        if f.sons[0].kind == tyNone:
-          result = isGeneric
-        else:
-          result = typeRel(c, f.sons[0], a.sons[0])
-        if result != isNone:
-          put(c.bindings, f, a)
+      # proc foo(T: typedesc, x: T)
+      # when `f` is an unresolved typedesc, `a` could be any
+      # type, so we should not perform this check earlier
+      if a.kind != tyTypeDesc: return isNone
+    
+      if f.base.kind == tyNone:
+        result = isGeneric
+      else:
+        result = typeRel(c, f.base, a.base)
+      
+      if result != isNone:
+        put(c.bindings, f, a)
+    else:
+      if tfUnresolved in f.flags:
+        result = typeRel(c, prev.base, a)
+      elif a.kind == tyTypeDesc:
+        result = typeRel(c, prev.base, a.base)
       else:
         result = isNone
+ 
+  of tyIter:
+    if a.kind == tyIter or 
+      (a.kind == tyProc and tfIterator in a.flags):
+      result = typeRel(c, f.base, a.base)
     else:
-      internalAssert prev.sonsLen == 1
-      let toMatch = if tfUnresolved in f.flags: a
-                    else: a.sons[0]
-      result = typeRel(c, prev.sons[0], toMatch)
-  
+      result = isNone
+
   of tyStmt:
     result = isGeneric
   
   of tyProxy:
     result = isEqual
+
+  of tyFromExpr:
+    # fix the expression, so it contains the already instantiated types
+    let instantiated = replaceTypesInBody(c.c, c.bindings, f.n)
+    let reevaluted = c.c.semExpr(c.c, instantiated)
+    case reevaluted.typ.kind
+    of tyTypeDesc:
+      result = typeRel(c, a, reevaluted.typ.base)
+    of tyStatic:
+      result = typeRel(c, a, reevaluted.typ.base)
+      if result != isNone and reevaluted.typ.n != nil:
+        if not exprStructuralEquivalent(aOrig.n, reevaluted.typ.n):
+          result = isNone
+    else:
+      localError(f.n.info, errTypeExpected)
+      result = isNone
   
-  else: internalError("typeRel: " & $f.kind)
+  else:
+    internalAssert false
   
 proc cmpTypes*(c: PContext, f, a: PType): TTypeRelation = 
   var m: TCandidate
@@ -981,6 +1083,10 @@ proc localConvMatch(c: PContext, m: var TCandidate, f, a: PType,
       result.typ = getInstantiatedType(c, arg, m, base(f))
     m.baseTypeMatch = true
 
+proc isInlineIterator*(t: PType): bool =
+  result = t.kind == tyIter or
+          (t.kind == tyBuiltInTypeClass and t.base.kind == tyIter)
+
 proc paramTypesMatchAux(m: var TCandidate, f, argType: PType,
                         argSemantized, argOrig: PNode): PNode =
   var
@@ -988,24 +1094,67 @@ proc paramTypesMatchAux(m: var TCandidate, f, argType: PType,
     arg = argSemantized
     argType = argType
     c = m.c
-
+ 
   if tfHasStatic in fMaybeStatic.flags:
     # XXX: When implicit statics are the default
     # this will be done earlier - we just have to
     # make sure that static types enter here
-    var evaluated = c.semTryConstExpr(c, arg)
-    if evaluated != nil:
-      arg.typ = newTypeS(tyStatic, c)
-      arg.typ.sons = @[evaluated.typ]
-      arg.typ.n = evaluated
-      argType = arg.typ
+     
+    # XXX: weaken tyGenericParam and call it tyGenericPlaceholder
+    # and finally start using tyTypedesc for generic types properly.
+    if argType.kind == tyGenericParam and tfWildcard in argType.flags:
+      argType.assignType(f)
+      # put(m.bindings, f, argType)
+      return argSemantized
+
+    if argType.kind == tyStatic:
+      if m.callee.kind == tyGenericBody:
+        result = newNodeI(nkType, argOrig.info)
+        result.typ = makeTypeFromExpr(c, arg)
+        return
+    else:
+      var evaluated = c.semTryConstExpr(c, arg)
+      if evaluated != nil:
+        arg.typ = newTypeS(tyStatic, c)
+        arg.typ.sons = @[evaluated.typ]
+        arg.typ.n = evaluated
+        argType = arg.typ
  
   var
-    a = if c.inTypeClass > 0: argType.skipTypes({tyTypeDesc})
+    a = if c.inTypeClass > 0: argType.skipTypes({tyTypeDesc, tyFieldAccessor})
         else: argType
  
     r = typeRel(m, f, a)
 
+  if r != isNone and m.calleeSym != nil and
+     m.calleeSym.kind in {skMacro, skTemplate}:
+    # XXX: duplicating this is ugly, maybe we should move this
+    # directly into typeRel using return-like templates
+    case r
+    of isConvertible, isIntConv: inc(m.convMatches)
+    of isSubtype, isSubrange: inc(m.subtypeMatches)
+    of isGeneric, isInferred: inc(m.genericMatches)
+    of isInferredConvertible: inc(m.genericMatches); inc(m.convMatches)
+    of isFromIntLit: inc(m.intConvMatches, 256)
+    of isEqual: inc(m.exactMatches)
+    of isNone: discard
+
+    if f.kind == tyStmt and argOrig.kind == nkDo:
+      return argOrig[bodyPos]
+    elif f.kind == tyTypeDesc:
+      return arg
+    elif f.kind == tyStatic:
+      return arg.typ.n
+    else:
+      return argOrig
+
+  if r != isNone and f.isInlineIterator:
+    var inlined = newTypeS(tyStatic, c)
+    inlined.sons = @[argType]
+    inlined.n = argSemantized
+    put(m.bindings, f, inlined)
+    return argSemantized
+
   case r
   of isConvertible:
     inc(m.convMatches)
@@ -1022,24 +1171,24 @@ proc paramTypesMatchAux(m: var TCandidate, f, argType: PType,
     inc(m.subtypeMatches)
     #result = copyTree(arg)
     result = implicitConv(nkHiddenStdConv, f, copyTree(arg), m, c)
-  of isGeneric:
+  of isInferred, isInferredConvertible:
     inc(m.genericMatches)
-    if m.calleeSym != nil and m.calleeSym.kind in {skMacro, skTemplate}:
-      if f.kind == tyStmt and argOrig.kind == nkDo:
-        result = argOrig[bodyPos]
-      elif f.kind == tyTypeDesc:
-        result = arg
-      elif f.kind == tyStatic:
-        result = arg.typ.n
-      else:
-        result = argOrig
+    if arg.kind in {nkProcDef, nkIteratorDef} + nkLambdaKinds:
+      result = c.semInferredLambda(c, m.bindings, arg)
     else:
-      result = copyTree(arg)
-      result.typ = getInstantiatedType(c, arg, m, f) 
-      # BUG: f may not be the right key!
-      if skipTypes(result.typ, abstractVar-{tyTypeDesc}).kind in {tyTuple}:
-        result = implicitConv(nkHiddenStdConv, f, copyTree(arg), m, c) 
-        # BUGFIX: use ``result.typ`` and not `f` here
+      let inferred = c.semGenerateInstance(c, arg.sym, m.bindings, arg.info)
+      result = newSymNode(inferred, arg.info)
+    if r == isInferredConvertible:
+      inc(m.convMatches)
+      result = implicitConv(nkHiddenStdConv, f, result, m, c)
+  of isGeneric:
+    inc(m.genericMatches)
+    result = copyTree(arg)
+    result.typ = getInstantiatedType(c, arg, m, f)
+    # BUG: f may not be the right key!
+    if skipTypes(result.typ, abstractVar-{tyTypeDesc}).kind in {tyTuple}:
+      result = implicitConv(nkHiddenStdConv, f, copyTree(arg), m, c)
+      # BUGFIX: use ``result.typ`` and not `f` here
   of isFromIntLit:
     # too lazy to introduce another ``*matches`` field, so we conflate
     # ``isIntConv`` and ``isIntLit`` here:
@@ -1082,6 +1231,7 @@ proc paramTypesMatch*(m: var TCandidate, f, a: PType,
     # incorrect to simply use the first fitting match. However, to implement
     # this correctly is inefficient. We have to copy `m` here to be able to
     # roll back the side effects of the unification algorithm.
+
     let c = m.c
     var x, y, z: TCandidate
     initCandidate(c, x, m.callee)
@@ -1092,7 +1242,7 @@ proc paramTypesMatch*(m: var TCandidate, f, a: PType,
     z.calleeSym = m.calleeSym
     var best = -1
     for i in countup(0, sonsLen(arg) - 1): 
-      if arg.sons[i].sym.kind in {skProc, skIterator, skMethod, skConverter}: 
+      if arg.sons[i].sym.kind in {skProc, skMethod, skConverter}+skIterators:
         copyCandidate(z, m)
         var r = typeRel(z, f, arg.sons[i].typ)
         if r != isNone: 
@@ -1103,10 +1253,10 @@ proc paramTypesMatch*(m: var TCandidate, f, a: PType,
             x.state = csMatch
           of csMatch: 
             var cmp = cmpCandidates(x, z)
-            if cmp < 0: 
+            if cmp < 0:
               best = i
               x = z
-            elif cmp == 0: 
+            elif cmp == 0:
               y = z           # z is as good as x
     if x.state == csEmpty: 
       result = nil
@@ -1132,7 +1282,9 @@ proc prepareOperand(c: PContext; formal: PType; a: PNode): PNode =
     # a.typ == nil is valid
     result = a
   elif a.typ.isNil:
-    result = c.semOperand(c, a, {efDetermineType})
+    let flags = if formal.kind == tyIter: {efDetermineType, efWantIterator}
+                else: {efDetermineType}
+    result = c.semOperand(c, a, flags)
   else:
     result = a
 
diff --git a/compiler/syntaxes.nim b/compiler/syntaxes.nim
index 7c44ec0b4..478c2a837 100644
--- a/compiler/syntaxes.nim
+++ b/compiler/syntaxes.nim
@@ -17,14 +17,15 @@ type
   TFilterKind* = enum 
     filtNone, filtTemplate, filtReplace, filtStrip
   TParserKind* = enum 
-    skinStandard, skinBraces, skinEndX
+    skinStandard, skinStrongSpaces, skinBraces, skinEndX
 
 const 
-  parserNames*: array[TParserKind, string] = ["standard", "braces", "endx"]
-  filterNames*: array[TFilterKind, string] = ["none", "stdtmpl", "replace", 
-    "strip"]
+  parserNames*: array[TParserKind, string] = ["standard", "strongspaces",
+                                              "braces", "endx"]
+  filterNames*: array[TFilterKind, string] = ["none", "stdtmpl", "replace",
+                                              "strip"]
 
-type 
+type
   TParsers*{.final.} = object 
     skin*: TParserKind
     parser*: TParser
@@ -54,7 +55,7 @@ proc parseFile(fileIdx: int32): PNode =
 
 proc parseAll(p: var TParsers): PNode = 
   case p.skin
-  of skinStandard: 
+  of skinStandard, skinStrongSpaces:
     result = parser.parseAll(p.parser)
   of skinBraces: 
     result = pbraces.parseAll(p.parser)
@@ -65,7 +66,7 @@ proc parseAll(p: var TParsers): PNode =
   
 proc parseTopLevelStmt(p: var TParsers): PNode = 
   case p.skin
-  of skinStandard: 
+  of skinStandard, skinStrongSpaces:
     result = parser.parseTopLevelStmt(p.parser)
   of skinBraces: 
     result = pbraces.parseTopLevelStmt(p.parser)
@@ -170,7 +171,9 @@ proc openParsers(p: var TParsers, fileIdx: int32, inputstream: PLLStream) =
   else: s = inputstream
   case p.skin
   of skinStandard, skinBraces, skinEndX:
-    parser.openParser(p.parser, fileIdx, s)
+    parser.openParser(p.parser, fileIdx, s, false)
+  of skinStrongSpaces:
+    parser.openParser(p.parser, fileIdx, s, true)
   
-proc closeParsers(p: var TParsers) = 
+proc closeParsers(p: var TParsers) =
   parser.closeParser(p.parser)
diff --git a/compiler/transf.nim b/compiler/transf.nim
index deb821eff..7922acbe9 100644
--- a/compiler/transf.nim
+++ b/compiler/transf.nim
@@ -20,10 +20,7 @@
 import 
   intsets, strutils, lists, options, ast, astalgo, trees, treetab, msgs, os, 
   idents, renderer, types, passes, semfold, magicsys, cgmeth, rodread,
-  lambdalifting, sempass2
-
-const 
-  genPrefix* = ":tmp"         # prefix for generated names
+  lambdalifting, sempass2, lowerings
 
 # implementation
 
@@ -113,7 +110,7 @@ proc newAsgnStmt(c: PTransf, le: PNode, ri: PTransNode): PTransNode =
   result[1] = ri
 
 proc transformSymAux(c: PTransf, n: PNode): PNode =
-  #if n.sym.kind == skIterator and n.sym.typ.callConv == ccClosure:
+  #if n.sym.kind == skClosureIterator:
   #  return liftIterSym(n)
   var b: PNode
   var tc = c.transCon
@@ -240,13 +237,6 @@ proc transformLoopBody(c: PTransf, n: PNode): PTransNode =
     discard c.contSyms.pop()
   else: 
     result = transform(c, n)
-  
-proc newTupleAccess(tup: PNode, i: int): PNode = 
-  result = newNodeIT(nkBracketExpr, tup.info, tup.typ.sons[i])
-  addSon(result, copyTree(tup))
-  var lit = newNodeIT(nkIntLit, tup.info, getSysType(tyInt))
-  lit.intVal = i
-  addSon(result, lit)
 
 proc unpackTuple(c: PTransf, n: PNode, father: PTransNode) = 
   # XXX: BUG: what if `n` is an expression with side-effects?
@@ -425,7 +415,7 @@ proc findWrongOwners(c: PTransf, n: PNode) =
         x.sym.owner.name.s & " " & getCurrOwner(c).name.s)
   else:
     for i in 0 .. <safeLen(n): findWrongOwners(c, n.sons[i])
-  
+
 proc transformFor(c: PTransf, n: PNode): PTransNode = 
   # generate access statements for the parameters (unless they are constant)
   # put mapping from formal parameters to actual parameters
@@ -433,13 +423,13 @@ proc transformFor(c: PTransf, n: PNode): PTransNode =
 
   var length = sonsLen(n)
   var call = n.sons[length - 2]
-  if call.kind notin nkCallKinds or call.sons[0].kind != nkSym or 
-      call.sons[0].typ.callConv == ccClosure or
-      call.sons[0].sym.kind != skIterator:
+  if call.typ.kind != tyIter and
+    (call.kind notin nkCallKinds or call.sons[0].kind != nkSym or 
+      call.sons[0].sym.kind != skIterator):
     n.sons[length-1] = transformLoopBody(c, n.sons[length-1]).PNode
     return lambdalifting.liftForLoop(n).PTransNode
     #InternalError(call.info, "transformFor")
-
+  
   #echo "transforming: ", renderTree(n)
   result = newTransNode(nkStmtList, n.info, 0)
   var loopBody = transformLoopBody(c, n.sons[length-1])
@@ -454,12 +444,13 @@ proc transformFor(c: PTransf, n: PNode): PTransNode =
   var newC = newTransCon(getCurrOwner(c))
   newC.forStmt = n
   newC.forLoopBody = loopBody
-  if iter.kind != skIterator: internalError(call.info, "transformFor") 
+  internalAssert iter.kind == skIterator
   # generate access statements for the parameters (unless they are constant)
   pushTransCon(c, newC)
   for i in countup(1, sonsLen(call) - 1): 
     var arg = transform(c, call.sons[i]).PNode
     var formal = skipTypes(iter.typ, abstractInst).n.sons[i].sym 
+    if arg.typ.kind == tyIter: continue
     case putArgInto(arg, formal.typ)
     of paDirectMapping: 
       idNodeTablePut(newC.mapping, formal, arg)
@@ -481,7 +472,7 @@ proc transformFor(c: PTransf, n: PNode): PTransNode =
   dec(c.inlining)
   popInfoContext()
   popTransCon(c)
-  #echo "transformed: ", renderTree(n)
+  # echo "transformed: ", result.PNode.renderTree
   
 proc getMagicOp(call: PNode): TMagic = 
   if call.sons[0].kind == nkSym and
@@ -741,7 +732,7 @@ proc transformBody*(module: PSym, n: PNode, prc: PSym): PNode =
     var c = openTransf(module, "")
     result = processTransf(c, n, prc)
     result = liftLambdas(prc, result)
-    #if prc.kind == skIterator and prc.typ.callConv == ccClosure:
+    #if prc.kind == skClosureIterator:
     #  result = lambdalifting.liftIterator(prc, result)
     incl(result.flags, nfTransf)
     when useEffectSystem: trackProc(prc, result)
@@ -754,6 +745,7 @@ proc transformStmt*(module: PSym, n: PNode): PNode =
     result = processTransf(c, n, module)
     result = liftLambdasForTopLevel(module, result)
     incl(result.flags, nfTransf)
+    when useEffectSystem: trackTopLevelStmt(module, result)
 
 proc transformExpr*(module: PSym, n: PNode): PNode =
   if nfTransf in n.flags:
diff --git a/compiler/types.nim b/compiler/types.nim
index db75cd3c0..ae31d24de 100644
--- a/compiler/types.nim
+++ b/compiler/types.nim
@@ -431,11 +431,12 @@ proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
       add(result, typeToString(t.sons[i]))
     add(result, ']')
   of tyTypeDesc:
-    if t.len == 0: result = "typedesc"
-    else: result = "typedesc[" & typeToString(t.sons[0]) & "]"
+    if t.base.kind == tyNone: result = "typedesc"
+    else: result = "typedesc[" & typeToString(t.base) & "]"
   of tyStatic:
     internalAssert t.len > 0
     result = "static[" & typeToString(t.sons[0]) & "]"
+    if t.n != nil: result.add "(" & renderTree(t.n) & ")"
   of tyUserTypeClass:
     internalAssert t.sym != nil and t.sym.owner != nil
     return t.sym.owner.name.s
@@ -452,7 +453,8 @@ proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
       of tyProc: "proc"
       of tyObject: "object"
       of tyTuple: "tuple"
-      else: (internalAssert(false); "")
+      of tyOpenArray: "openarray"
+      else: typeToStr[t.base.kind]
   of tyUserTypeClassInst:
     let body = t.base
     result = body.sym.name.s & "["
@@ -463,7 +465,7 @@ proc typeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
   of tyAnd:
     result = typeToString(t.sons[0]) & " and " & typeToString(t.sons[1])
   of tyOr:
-    result = typeToString(t.sons[0]) & " and " & typeToString(t.sons[1])
+    result = typeToString(t.sons[0]) & " or " & typeToString(t.sons[1])
   of tyNot:
     result = "not " & typeToString(t.sons[0])
   of tyExpr:
@@ -828,6 +830,12 @@ proc sameChildrenAux(a, b: PType, c: var TSameTypeClosure): bool =
     result = sameTypeOrNilAux(a.sons[i], b.sons[i], c)
     if not result: return 
 
+proc isGenericAlias*(t: PType): bool =
+  return t.kind == tyGenericInst and t.lastSon.kind == tyGenericInst
+
+proc skipGenericAlias*(t: PType): PType =
+  return if t.isGenericAlias: t.lastSon else: t
+
 proc sameTypeAux(x, y: PType, c: var TSameTypeClosure): bool =
   template cycleCheck() =
     # believe it or not, the direct check for ``containsOrIncl(c, a, b)``
@@ -857,7 +865,20 @@ proc sameTypeAux(x, y: PType, c: var TSameTypeClosure): bool =
       if a.kind != b.kind: return false
     of dcEqOrDistinctOf:
       while a.kind == tyDistinct: a = a.sons[0]
-      if a.kind != b.kind: return false  
+      if a.kind != b.kind: return false
+  
+  if x.kind == tyGenericInst:
+    let
+      lhs = x.skipGenericAlias
+      rhs = y.skipGenericAlias
+    if rhs.kind != tyGenericInst or lhs.base != rhs.base:
+      return false
+    for i in 1 .. lhs.len - 2:
+      let ff = rhs.sons[i]
+      let aa = lhs.sons[i]
+      if not sameTypeAux(ff, aa, c): return false
+    return true
+
   case a.kind
   of tyEmpty, tyChar, tyBool, tyNil, tyPointer, tyString, tyCString,
      tyInt..tyBigNum, tyStmt, tyExpr:
@@ -882,8 +903,6 @@ proc sameTypeAux(x, y: PType, c: var TSameTypeClosure): bool =
   of tyTuple:
     cycleCheck()
     result = sameTuple(a, b, c) and sameFlags(a, b)
-  of tyGenericInst:    
-    result = sameTypeAux(lastSon(a), lastSon(b), c)
   of tyTypeDesc:
     if c.cmp == dcEqIgnoreDistinct: result = false
     elif ExactTypeDescValues in c.flags:
@@ -910,6 +929,7 @@ proc sameTypeAux(x, y: PType, c: var TSameTypeClosure): bool =
     result = sameTypeOrNilAux(a.sons[0], b.sons[0], c) and
         sameValue(a.n.sons[0], b.n.sons[0]) and
         sameValue(a.n.sons[1], b.n.sons[1])
+  of tyGenericInst: discard
   of tyNone: result = false  
 
 proc sameBackendType*(x, y: PType): bool =
@@ -1003,12 +1023,6 @@ proc matchType*(a: PType, pattern: openArray[tuple[k:TTypeKind, i:int]],
     a = a.sons[i]
   result = a.kind == last
 
-proc isGenericAlias*(t: PType): bool =
-  return t.kind == tyGenericInst and t.lastSon.kind == tyGenericInst
-
-proc skipGenericAlias*(t: PType): PType =
-  return if t.isGenericAlias: t.lastSon else: t
-
 proc typeAllowedAux(marker: var TIntSet, typ: PType, kind: TSymKind,
                     flags: TTypeAllowedFlags = {}): bool =
   assert(kind in {skVar, skLet, skConst, skParam, skResult})
@@ -1042,7 +1056,8 @@ proc typeAllowedAux(marker: var TIntSet, typ: PType, kind: TSymKind,
   of tyEmpty:
     result = taField in flags
   of tyTypeClasses:
-    result = true
+    result = tfGenericTypeParam in t.flags or
+             taField notin flags
   of tyGenericBody, tyGenericParam, tyGenericInvokation,
      tyNone, tyForward, tyFromExpr, tyFieldAccessor:
     result = false
@@ -1231,8 +1246,7 @@ proc computeSizeAux(typ: PType, a: var BiggestInt): BiggestInt =
   of tyGenericInst, tyDistinct, tyGenericBody, tyMutable, tyConst, tyIter:
     result = computeSizeAux(lastSon(typ), a)
   of tyTypeDesc:
-    result = if typ.len == 1: computeSizeAux(typ.sons[0], a)
-             else: szUnknownSize
+    result = computeSizeAux(typ.base, a)
   of tyForward: return szIllegalRecursion
   else:
     #internalError("computeSizeAux()")
@@ -1246,7 +1260,7 @@ proc computeSize(typ: PType): BiggestInt =
 
 proc getReturnType*(s: PSym): PType =
   # Obtains the return type of a iterator/proc/macro/template
-  assert s.kind in {skProc, skTemplate, skMacro, skIterator}
+  assert s.kind in skProcKinds
   result = s.typ.sons[0]
 
 proc getSize(typ: PType): BiggestInt = 
@@ -1254,15 +1268,18 @@ proc getSize(typ: PType): BiggestInt =
   if result < 0: internalError("getSize: " & $typ.kind)
 
 proc containsGenericTypeIter(t: PType, closure: PObject): bool =
-  if t.kind in GenericTypes + tyTypeClasses + {tyFromExpr}:
-    return true
+  if t.kind == tyStatic:
+    return t.n == nil
 
   if t.kind == tyTypeDesc:
-    if t.sons[0].kind == tyNone: return true
+    if t.base.kind == tyNone: return true
     if containsGenericTypeIter(t.base, closure): return true
     return false
-  
-  return t.kind == tyStatic and t.n == nil
+
+  if t.kind in GenericTypes + tyTypeClasses + {tyFromExpr}:
+    return true
+
+  return false
 
 proc containsGenericType*(t: PType): bool = 
   result = iterOverType(t, containsGenericTypeIter, nil)
diff --git a/compiler/vm.nim b/compiler/vm.nim
index 10ac7aaaf..0d5386502 100644
--- a/compiler/vm.nim
+++ b/compiler/vm.nim
@@ -1,14 +1,16 @@
 #
 #
 #           The Nimrod Compiler
-#        (c) Copyright 2013 Andreas Rumpf
+#        (c) Copyright 2014 Andreas Rumpf
 #
 #    See the file "copying.txt", included in this
 #    distribution, for details about the copyright.
 #
 
 ## This file implements the new evaluation engine for Nimrod code.
-## An instruction is 1-2 int32s in memory, it is a register based VM.
+## An instruction is 1-3 int32s in memory, it is a register based VM.
+
+const debugEchoCode = false
 
 import ast except getstr
 
@@ -23,10 +25,22 @@ when hasFFI:
   import evalffi
 
 type
+  TRegisterKind = enum
+    rkNone, rkNode, rkInt, rkFloat, rkRegisterAddr, rkNodeAddr
+  TFullReg = object   # with a custom mark proc, we could use the same
+                      # data representation as LuaJit (tagged NaNs).
+    case kind: TRegisterKind
+    of rkNone: nil
+    of rkInt: intVal: BiggestInt
+    of rkFloat: floatVal: BiggestFloat
+    of rkNode: node: PNode
+    of rkRegisterAddr: regAddr: ptr TFullReg
+    of rkNodeAddr: nodeAddr: ptr PNode
+
   PStackFrame* = ref TStackFrame
   TStackFrame* = object
     prc: PSym                 # current prc; proc that is evaluated
-    slots: TNodeSeq           # parameters passed to the proc + locals;
+    slots: seq[TFullReg]      # parameters passed to the proc + locals;
                               # parameters come first
     next: PStackFrame         # for stacking
     comesFrom: int
@@ -54,7 +68,9 @@ proc stackTrace(c: PCtx, tos: PStackFrame, pc: int,
                 msg: TMsgKind, arg = "") =
   msgWriteln("stack trace: (most recent call last)")
   stackTraceAux(c, tos, pc)
-  localError(c.debug[pc], msg, arg)
+  # XXX test if we want 'globalError' for every mode
+  if c.mode == emRepl: globalError(c.debug[pc], msg, arg)
+  else: localError(c.debug[pc], msg, arg)
 
 proc bailOut(c: PCtx; tos: PStackFrame) =
   stackTrace(c, tos, c.exceptionInstr, errUnhandledExceptionX,
@@ -63,24 +79,9 @@ proc bailOut(c: PCtx; tos: PStackFrame) =
 when not defined(nimComputedGoto):
   {.pragma: computedGoto.}
 
-proc myreset(n: PNode) =
+proc myreset(n: var TFullReg) =
   when defined(system.reset): 
-    var oldInfo = n.info
-    reset(n[])
-    n.info = oldInfo
-
-proc skipMeta(n: PNode): PNode = (if n.kind != nkMetaNode: n else: n.sons[0])
-
-proc setMeta(n, child: PNode) =
-  assert n.kind == nkMetaNode
-  let child = child.skipMeta
-  if n.sons.isNil: n.sons = @[child]
-  else: n.sons[0] = child
-
-proc uast(n: PNode): PNode {.inline.} =
-  # "underlying ast"
-  assert n.kind == nkMetaNode
-  n.sons[0]
+    reset(n)
 
 template ensureKind(k: expr) {.immediate, dirty.} =
   if regs[ra].kind != k:
@@ -112,23 +113,32 @@ template decodeBx(k: expr) {.immediate, dirty.} =
 template move(a, b: expr) {.immediate, dirty.} = system.shallowCopy(a, b)
 # XXX fix minor 'shallowCopy' overloading bug in compiler
 
-proc moveConst(x, y: PNode) =
+proc createStrKeepNode(x: var TFullReg) =
+  if x.node.isNil:
+    x.node = newNode(nkStrLit)
+  elif x.node.kind == nkNilLit:
+    system.reset(x.node[])
+    x.node.kind = nkStrLit
+  elif x.node.kind notin {nkStrLit..nkTripleStrLit}:
+    # XXX this is hacky; tests/txmlgen triggers it:
+    x.node = newNode(nkStrLit)
+    #  debug x.node
+    #assert x.node.kind in {nkStrLit..nkTripleStrLit}
+
+template createStr(x) =
+  x.node = newNode(nkStrLit)
+
+proc moveConst(x: var TFullReg, y: TFullReg) =
   if x.kind != y.kind:
     myreset(x)
     x.kind = y.kind
-  x.typ = y.typ
   case x.kind
-  of nkCharLit..nkInt64Lit: x.intVal = y.intVal
-  of nkFloatLit..nkFloat64Lit: x.floatVal = y.floatVal
-  of nkStrLit..nkTripleStrLit: move(x.strVal, y.strVal)
-  of nkIdent: x.ident = y.ident
-  of nkSym: x.sym = y.sym
-  of nkMetaNode:
-    if x.sons.isNil: x.sons = @[y.sons[0]]
-    else: x.sons[0] = y.sons[0]
-  else:
-    if x.kind notin {nkEmpty..nkNilLit}:
-      move(x.sons, y.sons)
+  of rkNone: discard
+  of rkInt: x.intVal = y.intVal
+  of rkFloat: x.floatVal = y.floatVal
+  of rkNode: x.node = y.node
+  of rkRegisterAddr: x.regAddr = y.regAddr
+  of rkNodeAddr: x.nodeAddr = y.nodeAddr
 
 # this seems to be the best way to model the reference semantics
 # of PNimrodNode:
@@ -155,29 +165,56 @@ proc copyValue(src: PNode): PNode =
     for i in countup(0, sonsLen(src) - 1):
       result.sons[i] = copyValue(src.sons[i])
 
-proc asgnComplex(x, y: PNode) =
+proc asgnComplex(x: var TFullReg, y: TFullReg) =
   if x.kind != y.kind:
     myreset(x)
     x.kind = y.kind
-  x.typ = y.typ
   case x.kind
-  of nkCharLit..nkInt64Lit: x.intVal = y.intVal
-  of nkFloatLit..nkFloat64Lit: x.floatVal = y.floatVal
-  of nkStrLit..nkTripleStrLit: x.strVal = y.strVal
-  of nkIdent: x.ident = y.ident
-  of nkSym: x.sym = y.sym
-  of nkMetaNode:
-    if x.sons.isNil: x.sons = @[y.sons[0]]
-    else: x.sons[0] = y.sons[0]
+  of rkNone: discard
+  of rkInt: x.intVal = y.intVal
+  of rkFloat: x.floatVal = y.floatVal
+  of rkNode: x.node = copyValue(y.node)
+  of rkRegisterAddr: x.regAddr = y.regAddr
+  of rkNodeAddr: x.nodeAddr = y.nodeAddr
+
+proc putIntoNode(n: var PNode; x: TFullReg) =
+  case x.kind
+  of rkNone: discard
+  of rkInt: n.intVal = x.intVal
+  of rkFloat: n.floatVal = x.floatVal
+  of rkNode:
+    if nfIsRef in x.node.flags: n = x.node
+    else: n[] = x.node[]
+  of rkRegisterAddr: putIntoNode(n, x.regAddr[])
+  of rkNodeAddr: n[] = x.nodeAddr[][]
+
+proc putIntoReg(dest: var TFullReg; n: PNode) =
+  case n.kind
+  of nkStrLit..nkTripleStrLit:
+    dest.kind = rkNode
+    createStr(dest)
+    dest.node.strVal = n.strVal
+  of nkCharLit..nkUInt64Lit:
+    dest.kind = rkInt
+    dest.intVal = n.intVal
+  of nkFloatLit..nkFloat128Lit:
+    dest.kind = rkFloat
+    dest.floatVal = n.floatVal
   else:
-    if x.kind notin {nkEmpty..nkNilLit}:
-      let y = y.copyValue
-      for i in countup(0, sonsLen(y) - 1): 
-        if i < x.len: x.sons[i] = y.sons[i]
-        else: addSon(x, y.sons[i])
+    dest.kind = rkNode
+    dest.node = n
+
+proc regToNode(x: TFullReg): PNode =
+  case x.kind
+  of rkNone: result = newNode(nkEmpty)
+  of rkInt: result = newNode(nkIntLit); result.intVal = x.intVal
+  of rkFloat: result = newNode(nkFloatLit); result.floatVal = x.floatVal
+  of rkNode: result = x.node
+  of rkRegisterAddr: result = regToNode(x.regAddr[])
+  of rkNodeAddr: result = x.nodeAddr[]
 
 template getstr(a: expr): expr =
-  (if a.kind in {nkStrLit..nkTripleStrLit}: a.strVal else: $chr(int(a.intVal)))
+  (if a.kind == rkNode: a.node.strVal else: $chr(int(a.intVal)))
 
 proc pushSafePoint(f: PStackFrame; pc: int) =
   if f.safePoints.isNil: f.safePoints = @[]
@@ -185,7 +222,7 @@ proc pushSafePoint(f: PStackFrame; pc: int) =
 
 proc popSafePoint(f: PStackFrame) = discard f.safePoints.pop()
 
-proc cleanUpOnException(c: PCtx; tos: PStackFrame; regs: TNodeSeq): int =
+proc cleanUpOnException(c: PCtx; tos: PStackFrame; regs: seq[TFullReg]): int =
   let raisedType = c.currentExceptionA.typ.skipTypes(abstractPtrs)
   var f = tos
   while true:
@@ -227,50 +264,65 @@ proc cleanUpOnReturn(c: PCtx; f: PStackFrame): int =
       return pc
   return -1
 
-proc opConv*(dest, src: PNode, typ: PType): bool =
-  if typ.kind == tyString:
-    if dest.kind != nkStrLit:
+proc opConv*(dest: var TFullReg, src: TFullReg, desttyp, srctyp: PType): bool =
+  if desttyp.kind == tyString:
+    if dest.kind != rkNode:
       myreset(dest)
-      dest.kind = nkStrLit
-    case src.typ.skipTypes(abstractRange).kind
-    of tyEnum: 
-      dest.strVal = ordinalValToString(src)
-    of tyInt..tyInt64, tyUInt..tyUInt64:
-      dest.strVal = $src.intVal
+      dest.kind = rkNode
+    dest.node = newNode(nkStrLit)
+    let styp = srctyp.skipTypes(abstractRange)
+    case styp.kind
+    of tyEnum:
+      let n = styp.n
+      let x = src.intVal.int
+      if x <% n.len and (let f = n.sons[x].sym; f.position == x):
+        dest.node.strVal = if f.ast.isNil: f.name.s else: f.ast.strVal
+      else:
+        for i in 0.. <n.len:
+          if n.sons[i].kind != nkSym: internalError("opConv for enum")
+          let f = n.sons[i].sym
+          if f.position == x:
+            dest.node.strVal = if f.ast.isNil: f.name.s else: f.ast.strVal
+            return
+        internalError("opConv for enum")
+    of tyInt..tyInt64:
+      dest.node.strVal = $src.intVal
+    of tyUInt..tyUInt64:
+      dest.node.strVal = $uint64(src.intVal)
     of tyBool:
-      dest.strVal = if src.intVal == 0: "false" else: "true"
+      dest.node.strVal = if src.intVal == 0: "false" else: "true"
     of tyFloat..tyFloat128:
-      dest.strVal = $src.floatVal
+      dest.node.strVal = $src.floatVal
     of tyString, tyCString:
-      dest.strVal = src.strVal
+      dest.node.strVal = src.node.strVal
     of tyChar:
-      dest.strVal = $chr(src.intVal)
+      dest.node.strVal = $chr(src.intVal)
     else:
-      internalError("cannot convert to string " & typ.typeToString)
+      internalError("cannot convert to string " & desttyp.typeToString)
   else:
-    case skipTypes(typ, abstractRange).kind
+    case skipTypes(desttyp, abstractRange).kind
     of tyInt..tyInt64:
-      if dest.kind != nkIntLit:
-        myreset(dest); dest.kind = nkIntLit
-      case skipTypes(src.typ, abstractRange).kind
+      if dest.kind != rkInt:
+        myreset(dest); dest.kind = rkInt
+      case skipTypes(srctyp, abstractRange).kind
       of tyFloat..tyFloat64:
         dest.intVal = system.toInt(src.floatVal)
       else:
         dest.intVal = src.intVal
-      if dest.intVal < firstOrd(typ) or dest.intVal > lastOrd(typ):
+      if dest.intVal < firstOrd(desttyp) or dest.intVal > lastOrd(desttyp):
         return true
     of tyUInt..tyUInt64:
-      if dest.kind != nkIntLit:
-        myreset(dest); dest.kind = nkIntLit
-      case skipTypes(src.typ, abstractRange).kind
+      if dest.kind != rkInt:
+        myreset(dest); dest.kind = rkInt
+      case skipTypes(srctyp, abstractRange).kind
       of tyFloat..tyFloat64:
         dest.intVal = system.toInt(src.floatVal)
       else:
-        dest.intVal = src.intVal and ((1 shl typ.size)-1)
+        dest.intVal = src.intVal and ((1 shl (desttyp.size*8))-1)
     of tyFloat..tyFloat64:
-      if dest.kind != nkFloatLit:
-        myreset(dest); dest.kind = nkFloatLit
-      case skipTypes(src.typ, abstractRange).kind
+      if dest.kind != rkFloat:
+        myreset(dest); dest.kind = rkFloat
+      case skipTypes(srctyp, abstractRange).kind
       of tyInt..tyInt64, tyUInt..tyUInt64, tyEnum, tyBool, tyChar: 
         dest.floatVal = toFloat(src.intVal.int)
       else:
@@ -280,25 +332,32 @@ proc opConv*(dest, src: PNode, typ: PType): bool =
 
 proc compile(c: PCtx, s: PSym): int = 
   result = vmgen.genProc(c, s)
+  when debugEchoCode: c.echoCode result
   #c.echoCode
 
-proc regsContents(regs: TNodeSeq) =
-  for i in 0.. <regs.len:
-    echo "Register ", i
-    #debug regs[i]
+template handleJmpBack() {.dirty.} =
+  if c.loopIterations <= 0:
+    if allowInfiniteLoops in c.features:
+      c.loopIterations = MaxLoopIterations
+    else:
+      msgWriteln("stack trace: (most recent call last)")
+      stackTraceAux(c, tos, pc)
+      globalError(c.debug[pc], errTooManyIterations)
+  dec(c.loopIterations)
 
-proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
+proc rawExecute(c: PCtx, start: int, tos: PStackFrame): TFullReg =
   var pc = start
   var tos = tos
-  var regs: TNodeSeq # alias to tos.slots for performance
+  var regs: seq[TFullReg] # alias to tos.slots for performance
   move(regs, tos.slots)
   #echo "NEW RUN ------------------------"
   while true:
     #{.computedGoto.}
     let instr = c.code[pc]
     let ra = instr.regA
-    #echo "PC ", pc, " ", c.code[pc].opcode, " ra ", ra
-    #message(c.debug[pc], warnUser, "gah")
+    #if c.traceActive:
+    #  echo "PC ", pc, " ", c.code[pc].opcode, " ra ", ra
+    #  message(c.debug[pc], warnUser, "Trace")
     case instr.opcode
     of opcEof: return regs[ra]
     of opcRet:
@@ -318,325 +377,348 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
     of opcYldYoid: assert false
     of opcYldVal: assert false
     of opcAsgnInt:
-      decodeB(nkIntLit)
+      decodeB(rkInt)
       regs[ra].intVal = regs[rb].intVal
     of opcAsgnStr:
-      if regs[instr.regB].kind == nkNilLit:
-        decodeB(nkNilLit)
-      else:
-        decodeB(nkStrLit)
-        regs[ra].strVal = regs[rb].strVal
+      decodeB(rkNode)
+      createStrKeepNode regs[ra]
+      regs[ra].node.strVal = regs[rb].node.strVal
     of opcAsgnFloat:
-      decodeB(nkFloatLit)
+      decodeB(rkFloat)
       regs[ra].floatVal = regs[rb].floatVal
     of opcAsgnComplex:
       asgnComplex(regs[ra], regs[instr.regB])
     of opcAsgnRef:
       asgnRef(regs[ra], regs[instr.regB])
-    of opcWrGlobalRef:
-      asgnRef(c.globals.sons[instr.regBx-wordExcess-1], regs[ra])
-    of opcWrGlobal:
-      asgnComplex(c.globals.sons[instr.regBx-wordExcess-1], regs[ra])
-    of opcLdArr, opcLdArrRef:
-      # a = b[c]
+    of opcRegToNode:
+      decodeB(rkNode)
+      putIntoNode(regs[ra].node, regs[rb])
+    of opcNodeToReg:
+      let ra = instr.regA
       let rb = instr.regB
-      let rc = instr.regC
+      # opcDeref might already have loaded it into a register. XXX Let's hope
+      # this is still correct this way:
+      if regs[rb].kind != rkNode:
+        regs[ra] = regs[rb]
+      else:
+        assert regs[rb].kind == rkNode
+        let nb = regs[rb].node
+        case nb.kind
+        of nkCharLit..nkInt64Lit:
+          ensureKind(rkInt)
+          regs[ra].intVal = nb.intVal
+        of nkFloatLit..nkFloat64Lit:
+          ensureKind(rkFloat)
+          regs[ra].floatVal = nb.floatVal
+        else:
+          ensureKind(rkNode)
+          regs[ra].node = nb
+    of opcLdArr:
+      # a = b[c]
+      decodeBC(rkNode)
       if regs[rc].intVal > high(int):
         stackTrace(c, tos, pc, errIndexOutOfBounds)
       let idx = regs[rc].intVal.int
       # XXX what if the array is not 0-based? -> codegen should insert a sub
-      assert regs[rb].kind != nkMetaNode
-      let src = regs[rb]
+      let src = regs[rb].node
       if src.kind notin {nkEmpty..nkNilLit} and idx <% src.len:
-        if instr.opcode == opcLdArrRef and false:
-          # XXX activate when seqs are fixed
-          asgnRef(regs[ra], src.sons[idx])
-        else:
-          asgnComplex(regs[ra], src.sons[idx])
+        regs[ra].node = src.sons[idx]
       else:
         stackTrace(c, tos, pc, errIndexOutOfBounds)
     of opcLdStrIdx:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       let idx = regs[rc].intVal.int
-      if idx <=% regs[rb].strVal.len:
-        regs[ra].intVal = regs[rb].strVal[idx].ord
+      if idx <=% regs[rb].node.strVal.len:
+        regs[ra].intVal = regs[rb].node.strVal[idx].ord
       else:
         stackTrace(c, tos, pc, errIndexOutOfBounds)
     of opcWrArr:
       # a[b] = c
-      let rb = instr.regB
-      let rc = instr.regC
+      decodeBC(rkNode)
       let idx = regs[rb].intVal.int
-      if idx <% regs[ra].len:
-        asgnComplex(regs[ra].sons[idx], regs[rc])
-      else:
-        stackTrace(c, tos, pc, errIndexOutOfBounds)
-    of opcWrArrRef:
-      let rb = instr.regB
-      let rc = instr.regC
-      let idx = regs[rb].intVal.int
-      if idx <% regs[ra].len:
-        asgnRef(regs[ra].sons[idx], regs[rc])
+      if idx <% regs[ra].node.len:
+        putIntoNode(regs[ra].node.sons[idx], regs[rc])
       else:
         stackTrace(c, tos, pc, errIndexOutOfBounds)
     of opcLdObj:
       # a = b.c
-      let rb = instr.regB
-      let rc = instr.regC
-      #Message(c.debug[pc], warnUser, $regs[rb].safeLen & " " & $rc)
-      asgnComplex(regs[ra], regs[rb].sons[rc])
-    of opcLdObjRef:
-      # a = b.c
-      let rb = instr.regB
-      let rc = instr.regC
-      # XXX activate when seqs are fixed
-      asgnComplex(regs[ra], regs[rb].sons[rc])
-      #asgnRef(regs[ra], regs[rb].sons[rc])
+      decodeBC(rkNode)
+      let src = regs[rb].node
+      if src.kind notin {nkEmpty..nkNilLit}:
+        let n = src.sons[rc]
+        regs[ra].node = n
+      else:
+        stackTrace(c, tos, pc, errNilAccess)
     of opcWrObj:
       # a.b = c
-      let rb = instr.regB
-      let rc = instr.regC
-      #if regs[ra].isNil or regs[ra].sons.isNil or rb >= len(regs[ra]):
-      #  debug regs[ra]
-      #  debug regs[rc]
-      #  echo "RB ", rb
-      #  internalError(c.debug[pc], "argl")
-      asgnComplex(regs[ra].sons[rb], regs[rc])
-    of opcWrObjRef:
-      let rb = instr.regB
-      let rc = instr.regC
-      asgnRef(regs[ra].sons[rb], regs[rc])
+      decodeBC(rkNode)
+      putIntoNode(regs[ra].node.sons[rb], regs[rc])
     of opcWrStrIdx:
-      decodeBC(nkStrLit)
+      decodeBC(rkNode)
       let idx = regs[rb].intVal.int
-      if idx <% regs[ra].strVal.len:
-        regs[ra].strVal[idx] = chr(regs[rc].intVal)
+      if idx <% regs[ra].node.strVal.len:
+        regs[ra].node.strVal[idx] = chr(regs[rc].intVal)
       else:
         stackTrace(c, tos, pc, errIndexOutOfBounds)
-    of opcAddr:
-      decodeB(nkRefTy)
-      if regs[ra].len == 0: regs[ra].add regs[rb]
-      else: regs[ra].sons[0] = regs[rb]
-    of opcDeref:
+    of opcAddrReg:
+      decodeB(rkRegisterAddr)
+      regs[ra].regAddr = addr(regs[rb])
+    of opcAddrNode:
+      decodeB(rkNodeAddr)
+      regs[ra].nodeAddr = addr(regs[rb].node)
+    of opcLdDeref:
       # a = b[]
+      let ra = instr.regA
       let rb = instr.regB
-      if regs[rb].kind == nkNilLit:
+      case regs[rb].kind
+      of rkNodeAddr:
+        ensureKind(rkNode)
+        regs[ra].node = regs[rb].nodeAddr[]
+      of rkRegisterAddr:
+        ensureKind(regs[rb].regAddr.kind)
+        regs[ra] = regs[rb].regAddr[]
+      of rkNode:
+        if regs[rb].node.kind == nkNilLit:
+          stackTrace(c, tos, pc, errNilAccess)
+        assert regs[rb].node.kind == nkRefTy
+        regs[ra].node = regs[rb].node.sons[0]
+      else:
         stackTrace(c, tos, pc, errNilAccess)
-      assert regs[rb].kind == nkRefTy
-      # XXX this is not correct
-      regs[ra] = regs[rb].sons[0]
+    of opcWrDeref:
+      # a[] = b
+      let ra = instr.regA
+      let rb = instr.regB
+      case regs[ra].kind
+      of rkNodeAddr: putIntoNode(regs[ra].nodeAddr[], regs[rb])
+      of rkRegisterAddr: regs[ra].regAddr[] = regs[rb]
+      of rkNode: putIntoNode(regs[ra].node, regs[rb])
+      else: stackTrace(c, tos, pc, errNilAccess)
     of opcAddInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal + regs[rc].intVal
     of opcAddImmInt:
-      decodeBImm(nkIntLit)
+      decodeBImm(rkInt)
+      #message(c.debug[pc], warnUser, "came here")
+      #debug regs[rb].node
       regs[ra].intVal = regs[rb].intVal + imm
     of opcSubInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal - regs[rc].intVal
     of opcSubImmInt:
-      decodeBImm(nkIntLit)
+      decodeBImm(rkInt)
       regs[ra].intVal = regs[rb].intVal - imm
     of opcLenSeq:
-      decodeBImm(nkIntLit)
+      decodeBImm(rkInt)
       #assert regs[rb].kind == nkBracket
       # also used by mNLen:
-      regs[ra].intVal = regs[rb].skipMeta.len - imm
+      regs[ra].intVal = regs[rb].node.safeLen - imm
     of opcLenStr:
-      decodeBImm(nkIntLit)
-      if regs[rb].kind == nkNilLit:
-        stackTrace(c, tos, pc, errNilAccess)
-      else:
-        assert regs[rb].kind in {nkStrLit..nkTripleStrLit}
-        regs[ra].intVal = regs[rb].strVal.len - imm
+      decodeBImm(rkInt)
+      assert regs[rb].kind == rkNode
+      regs[ra].intVal = regs[rb].node.strVal.len - imm
     of opcIncl:
-      decodeB(nkCurly)
-      if not inSet(regs[ra], regs[rb]): addSon(regs[ra], copyTree(regs[rb]))
+      decodeB(rkNode)
+      let b = regs[rb].regToNode
+      if not inSet(regs[ra].node, b):
+        addSon(regs[ra].node, copyTree(b))
     of opcInclRange:
-      decodeBC(nkCurly)
+      decodeBC(rkNode)
       var r = newNode(nkRange)
-      r.add regs[rb]
-      r.add regs[rc]
-      addSon(regs[ra], r.copyTree)
+      r.add regs[rb].regToNode
+      r.add regs[rc].regToNode
+      addSon(regs[ra].node, r.copyTree)
     of opcExcl:
-      decodeB(nkCurly)
-      var b = newNodeIT(nkCurly, regs[rb].info, regs[rb].typ)
-      addSon(b, regs[rb])
-      var r = diffSets(regs[ra], b)
-      discardSons(regs[ra])
-      for i in countup(0, sonsLen(r) - 1): addSon(regs[ra], r.sons[i])
+      decodeB(rkNode)
+      var b = newNodeIT(nkCurly, regs[rb].node.info, regs[rb].node.typ)
+      addSon(b, regs[rb].regToNode)
+      var r = diffSets(regs[ra].node, b)
+      discardSons(regs[ra].node)
+      for i in countup(0, sonsLen(r) - 1): addSon(regs[ra].node, r.sons[i])
     of opcCard:
-      decodeB(nkIntLit)
-      regs[ra].intVal = nimsets.cardSet(regs[rb])
+      decodeB(rkInt)
+      regs[ra].intVal = nimsets.cardSet(regs[rb].node)
     of opcMulInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal * regs[rc].intVal
     of opcDivInt:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = regs[rb].intVal div regs[rc].intVal
+      decodeBC(rkInt)
+      if regs[rc].intVal == 0: stackTrace(c, tos, pc, errConstantDivisionByZero)
+      else: regs[ra].intVal = regs[rb].intVal div regs[rc].intVal
     of opcModInt:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = regs[rb].intVal mod regs[rc].intVal
+      decodeBC(rkInt)
+      if regs[rc].intVal == 0: stackTrace(c, tos, pc, errConstantDivisionByZero)
+      else: regs[ra].intVal = regs[rb].intVal mod regs[rc].intVal
     of opcAddFloat:
-      decodeBC(nkFloatLit)
+      decodeBC(rkFloat)
       regs[ra].floatVal = regs[rb].floatVal + regs[rc].floatVal
     of opcSubFloat:
-      decodeBC(nkFloatLit)
+      decodeBC(rkFloat)
       regs[ra].floatVal = regs[rb].floatVal - regs[rc].floatVal
     of opcMulFloat:
-      decodeBC(nkFloatLit)
+      decodeBC(rkFloat)
       regs[ra].floatVal = regs[rb].floatVal * regs[rc].floatVal
     of opcDivFloat:
-      decodeBC(nkFloatLit)
+      decodeBC(rkFloat)
       regs[ra].floatVal = regs[rb].floatVal / regs[rc].floatVal
     of opcShrInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal shr regs[rc].intVal
     of opcShlInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal shl regs[rc].intVal
     of opcBitandInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal and regs[rc].intVal
     of opcBitorInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal or regs[rc].intVal
     of opcBitxorInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal xor regs[rc].intVal
     of opcAddu:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal +% regs[rc].intVal
     of opcSubu:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal -% regs[rc].intVal
     of opcMulu: 
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal *% regs[rc].intVal
     of opcDivu:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal /% regs[rc].intVal
     of opcModu:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = regs[rb].intVal %% regs[rc].intVal
     of opcEqInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].intVal == regs[rc].intVal)
     of opcLeInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].intVal <= regs[rc].intVal)
     of opcLtInt:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].intVal < regs[rc].intVal)
     of opcEqFloat:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].floatVal == regs[rc].floatVal)
     of opcLeFloat:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].floatVal <= regs[rc].floatVal)
     of opcLtFloat:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].floatVal < regs[rc].floatVal)
     of opcLeu:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].intVal <=% regs[rc].intVal)
     of opcLtu:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].intVal <% regs[rc].intVal)
     of opcEqRef:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord((regs[rb].kind == nkNilLit and
-                             regs[rc].kind == nkNilLit) or
-                             regs[rb].sons == regs[rc].sons)
+      decodeBC(rkInt)
+      regs[ra].intVal = ord((regs[rb].node.kind == nkNilLit and
+                             regs[rc].node.kind == nkNilLit) or
+                             regs[rb].node == regs[rc].node)
     of opcEqNimrodNode:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(regs[rb].skipMeta == regs[rc].skipMeta)
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(regs[rb].node == regs[rc].node)
     of opcXor:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       regs[ra].intVal = ord(regs[rb].intVal != regs[rc].intVal)
     of opcNot:
-      decodeB(nkIntLit)
-      assert regs[rb].kind == nkIntLit
+      decodeB(rkInt)
+      assert regs[rb].kind == rkInt
       regs[ra].intVal = 1 - regs[rb].intVal
     of opcUnaryMinusInt:
-      decodeB(nkIntLit)
-      assert regs[rb].kind == nkIntLit
+      decodeB(rkInt)
+      assert regs[rb].kind == rkInt
       regs[ra].intVal = -regs[rb].intVal
     of opcUnaryMinusFloat:
-      decodeB(nkFloatLit)
-      assert regs[rb].kind == nkFloatLit
+      decodeB(rkFloat)
+      assert regs[rb].kind == rkFloat
       regs[ra].floatVal = -regs[rb].floatVal
     of opcBitnotInt:
-      decodeB(nkIntLit)
-      assert regs[rb].kind == nkIntLit
+      decodeB(rkInt)
+      assert regs[rb].kind == rkInt
       regs[ra].intVal = not regs[rb].intVal
     of opcEqStr:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(regs[rb].strVal == regs[rc].strVal)
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(regs[rb].node.strVal == regs[rc].node.strVal)
     of opcLeStr:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(regs[rb].strVal <= regs[rc].strVal)
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(regs[rb].node.strVal <= regs[rc].node.strVal)
     of opcLtStr:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(regs[rb].strVal < regs[rc].strVal)
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(regs[rb].node.strVal < regs[rc].node.strVal)
     of opcLeSet:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(containsSets(regs[rb], regs[rc]))
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(containsSets(regs[rb].node, regs[rc].node))
     of opcEqSet: 
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(equalSets(regs[rb], regs[rc]))
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(equalSets(regs[rb].node, regs[rc].node))
     of opcLtSet:
-      decodeBC(nkIntLit)
-      let a = regs[rb]
-      let b = regs[rc]
+      decodeBC(rkInt)
+      let a = regs[rb].node
+      let b = regs[rc].node
       regs[ra].intVal = ord(containsSets(a, b) and not equalSets(a, b))
     of opcMulSet:
-      decodeBC(nkCurly)
-      move(regs[ra].sons, nimsets.intersectSets(regs[rb], regs[rc]).sons)
+      decodeBC(rkNode)
+      move(regs[ra].node.sons, 
+            nimsets.intersectSets(regs[rb].node, regs[rc].node).sons)
     of opcPlusSet: 
-      decodeBC(nkCurly)
-      move(regs[ra].sons, nimsets.unionSets(regs[rb], regs[rc]).sons)
+      decodeBC(rkNode)
+      move(regs[ra].node.sons,
+           nimsets.unionSets(regs[rb].node, regs[rc].node).sons)
     of opcMinusSet:
-      decodeBC(nkCurly)
-      move(regs[ra].sons, nimsets.diffSets(regs[rb], regs[rc]).sons)
+      decodeBC(rkNode)
+      move(regs[ra].node.sons,
+           nimsets.diffSets(regs[rb].node, regs[rc].node).sons)
     of opcSymdiffSet:
-      decodeBC(nkCurly)
-      move(regs[ra].sons, nimsets.symdiffSets(regs[rb], regs[rc]).sons)    
+      decodeBC(rkNode)
+      move(regs[ra].node.sons,
+           nimsets.symdiffSets(regs[rb].node, regs[rc].node).sons)    
     of opcConcatStr:
-      decodeBC(nkStrLit)
-      regs[ra].strVal = getstr(regs[rb])
+      decodeBC(rkNode)
+      createStr regs[ra]
+      regs[ra].node.strVal = getstr(regs[rb])
       for i in rb+1..rb+rc-1:
-        regs[ra].strVal.add getstr(regs[i])
+        regs[ra].node.strVal.add getstr(regs[i])
     of opcAddStrCh:
-      decodeB(nkStrLit)
-      regs[ra].strVal.add(regs[rb].intVal.chr)
+      decodeB(rkNode)
+      createStrKeepNode regs[ra]
+      regs[ra].node.strVal.add(regs[rb].intVal.chr)
     of opcAddStrStr:
-      decodeB(nkStrLit)
-      regs[ra].strVal.add(regs[rb].strVal)
+      decodeB(rkNode)
+      createStrKeepNode regs[ra]
+      regs[ra].node.strVal.add(regs[rb].node.strVal)
     of opcAddSeqElem:
-      decodeB(nkBracket)
-      regs[ra].add(copyTree(regs[rb]))
+      decodeB(rkNode)
+      if regs[ra].node.kind == nkBracket:
+        regs[ra].node.add(copyTree(regs[rb].regToNode))
+      else:
+        stackTrace(c, tos, pc, errNilAccess)
     of opcEcho:
       let rb = instr.regB
       for i in ra..ra+rb-1:
-        #if regs[i].kind != nkStrLit: debug regs[i]
-        write(stdout, regs[i].strVal)
+        #if regs[i].kind != rkNode: debug regs[i]
+        write(stdout, regs[i].node.strVal)
       writeln(stdout, "")
     of opcContainsSet:
-      decodeBC(nkIntLit)
-      regs[ra].intVal = ord(inSet(regs[rb], regs[rc]))
+      decodeBC(rkInt)
+      regs[ra].intVal = ord(inSet(regs[rb].node, regs[rc].regToNode))
     of opcSubStr:
-      decodeBC(nkStrLit)
+      decodeBC(rkNode)
       inc pc
       assert c.code[pc].opcode == opcSubStr
       let rd = c.code[pc].regA
-      regs[ra].strVal = substr(regs[rb].strVal, regs[rc].intVal.int, 
-                               regs[rd].intVal.int)
+      createStr regs[ra]
+      regs[ra].node.strVal = substr(regs[rb].node.strVal, 
+                                    regs[rc].intVal.int, regs[rd].intVal.int)
     of opcRangeChck:
       let rb = instr.regB
       let rc = instr.regC
-      if not (leValueConv(regs[rb], regs[ra]) and
-              leValueConv(regs[ra], regs[rc])):
+      if not (leValueConv(regs[rb].regToNode, regs[ra].regToNode) and
+              leValueConv(regs[ra].regToNode, regs[rc].regToNode)):
         stackTrace(c, tos, pc, errGenerated,
           msgKindToString(errIllegalConvFromXtoY) % [
           "unknown type" , "unknown type"])
@@ -644,8 +726,9 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
       # dest = call regStart, n; where regStart = fn, arg1, ...
       let rb = instr.regB
       let rc = instr.regC
-      let isClosure = regs[rb].kind == nkPar
-      let prc = if not isClosure: regs[rb].sym else: regs[rb].sons[0].sym
+      let bb = regs[rb].node
+      let isClosure = bb.kind == nkPar
+      let prc = if not isClosure: bb.sym else: bb.sons[0].sym
       if sfImportc in prc.flags:
         if allowFFI notin c.features:
           globalError(c.debug[pc], errGenerated, "VM not allowed to do FFI")
@@ -659,24 +742,27 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
                                              rb+1, rc-1, c.debug[pc])
           if newValue.kind != nkEmpty:
             assert instr.opcode == opcIndCallAsgn
-            asgnRef(regs[ra], newValue)
+            putIntoReg(regs[ra], newValue)
         else:
           globalError(c.debug[pc], errGenerated, "VM not built with FFI support")
       elif prc.kind != skTemplate:
         let newPc = compile(c, prc)
+        # tricky: a recursion is also a jump back, so we use the same
+        # logic as for loops:
+        if newPc < pc: handleJmpBack()
         #echo "new pc ", newPc, " calling: ", prc.name.s
         var newFrame = PStackFrame(prc: prc, comesFrom: pc, next: tos)
         newSeq(newFrame.slots, prc.offset)
         if not isEmptyType(prc.typ.sons[0]) or prc.kind == skMacro:
-          newFrame.slots[0] = getNullValue(prc.typ.sons[0], prc.info)
-        # pass every parameter by var (the language definition allows this):
+          putIntoReg(newFrame.slots[0], getNullValue(prc.typ.sons[0], prc.info))
         for i in 1 .. rc-1:
           newFrame.slots[i] = regs[rb+i]
         if isClosure:
-          newFrame.slots[rc] = regs[rb].sons[1]
+          newFrame.slots[rc].kind = rkNode
+          newFrame.slots[rc].node = regs[rb].node.sons[1]
         # allocate the temporaries:
-        for i in rc+ord(isClosure) .. <prc.offset:
-          newFrame.slots[i] = newNode(nkEmpty)
+        #for i in rc+ord(isClosure) .. <prc.offset:
+        #  newFrame.slots[i] = newNode(nkEmpty)
         tos = newFrame
         move(regs, newFrame.slots)
         # -1 for the following 'inc pc'
@@ -689,10 +775,10 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
                             c.module
         var macroCall = newNodeI(nkCall, c.debug[pc])
         macroCall.add(newSymNode(prc))
-        for i in 1 .. rc-1: macroCall.add(regs[rb+i].skipMeta)
+        for i in 1 .. rc-1: macroCall.add(regs[rb+i].regToNode)
         let a = evalTemplate(macroCall, prc, genSymOwner)
-        ensureKind(nkMetaNode)
-        setMeta(regs[ra], a)
+        ensureKind(rkNode)
+        regs[ra].node = a
     of opcTJmp:
       # jump Bx if A != 0
       let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
@@ -707,12 +793,16 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
       # jump Bx
       let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
       inc pc, rbx
+    of opcJmpBack:
+      let rbx = instr.regBx - wordExcess - 1 # -1 for the following 'inc pc'
+      inc pc, rbx
+      handleJmpBack()
     of opcBranch:
       # we know the next instruction is a 'fjmp':
       let branch = c.constants[instr.regBx-wordExcess]
       var cond = false
       for j in countup(0, sonsLen(branch) - 2): 
-        if overlap(regs[ra], branch.sons[j]): 
+        if overlap(regs[ra].regToNode, branch.sons[j]): 
           cond = true
           break
       assert c.code[pc+1].opcode == opcFJmp
@@ -741,7 +831,7 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
           bailOut(c, tos)
           return
     of opcRaise:
-      let raised = regs[ra]
+      let raised = regs[ra].node
       c.currentExceptionA = raised
       c.exceptionInstr = pc
       # -1 because of the following 'inc'
@@ -750,332 +840,377 @@ proc rawExecute(c: PCtx, start: int, tos: PStackFrame): PNode =
         bailOut(c, tos)
         return
     of opcNew:
+      ensureKind(rkNode)
       let typ = c.types[instr.regBx - wordExcess]
-      regs[ra] = getNullValue(typ, regs[ra].info)
-      regs[ra].flags.incl nfIsRef
+      regs[ra].node = getNullValue(typ, c.debug[pc])
+      regs[ra].node.flags.incl nfIsRef
     of opcNewSeq:
       let typ = c.types[instr.regBx - wordExcess]
       inc pc
-      ensureKind(nkBracket)
+      ensureKind(rkNode)
       let instr2 = c.code[pc]
       let count = regs[instr2.regA].intVal.int
-      regs[ra].typ = typ
-      newSeq(regs[ra].sons, count)
+      regs[ra].node = newNodeI(nkBracket, c.debug[pc])
+      regs[ra].node.typ = typ
+      newSeq(regs[ra].node.sons, count)
       for i in 0 .. <count:
-        regs[ra].sons[i] = getNullValue(typ.sons[0], regs[ra].info)
+        regs[ra].node.sons[i] = getNullValue(typ.sons[0], c.debug[pc])
     of opcNewStr:
-      decodeB(nkStrLit)
-      regs[ra].strVal = newString(regs[rb].intVal.int)
+      decodeB(rkNode)
+      regs[ra].node = newNodeI(nkStrLit, c.debug[pc])
+      regs[ra].node.strVal = newString(regs[rb].intVal.int)
     of opcLdImmInt:
       # dest = immediate value
-      decodeBx(nkIntLit)
+      decodeBx(rkInt)
       regs[ra].intVal = rbx
     of opcLdNull:
+      ensureKind(rkNode)
+      let typ = c.types[instr.regBx - wordExcess]
+      regs[ra].node = getNullValue(typ, c.debug[pc])
+      # opcLdNull really is the gist of the VM's problems: should it load
+      # a fresh null to  regs[ra].node  or to regs[ra].node[]? This really
+      # depends on whether regs[ra] represents the variable itself or wether
+      # it holds the indirection! Due to the way registers are re-used we cannot
+      # say for sure here! --> The codegen has to deal with it
+      # via 'genAsgnPatch'.
+    of opcLdNullReg:
       let typ = c.types[instr.regBx - wordExcess]
-      regs[ra] = getNullValue(typ, c.debug[pc])
+      if typ.skipTypes(abstractInst+{tyRange}-{tyTypeDesc}).kind in {
+          tyFloat..tyFloat128}:
+        ensureKind(rkFloat)
+        regs[ra].floatVal = 0.0
+      else:
+        ensureKind(rkInt)
+        regs[ra].intVal = 0
     of opcLdConst:
       let rb = instr.regBx - wordExcess
-      if regs[ra].isNil:
-        regs[ra] = copyTree(c.constants.sons[rb])
+      let cnst = c.constants.sons[rb]
+      if fitsRegister(cnst.typ):
+        putIntoReg(regs[ra], cnst)
       else:
-        moveConst(regs[ra], c.constants.sons[rb])
+        ensureKind(rkNode)
+        regs[ra].node = cnst
     of opcAsgnConst:
       let rb = instr.regBx - wordExcess
-      if regs[ra].isNil:
-        regs[ra] = copyTree(c.constants.sons[rb])
+      let cnst = c.constants.sons[rb]
+      if fitsRegister(cnst.typ):
+        putIntoReg(regs[ra], cnst)
       else:
-        asgnComplex(regs[ra], c.constants.sons[rb])
+        ensureKind(rkNode)
+        regs[ra].node = cnst.copyTree
     of opcLdGlobal:
       let rb = instr.regBx - wordExcess - 1
-      if regs[ra].isNil:
-        regs[ra] = copyTree(c.globals.sons[rb])
-      else:
-        asgnComplex(regs[ra], c.globals.sons[rb])
+      ensureKind(rkNode)
+      regs[ra].node = c.globals.sons[rb]
+    of opcLdGlobalAddr:
+      let rb = instr.regBx - wordExcess - 1
+      ensureKind(rkNodeAddr)
+      regs[ra].nodeAddr = addr(c.globals.sons[rb])
     of opcRepr:
-      decodeB(nkStrLit)
-      regs[ra].strVal = renderTree(regs[rb].skipMeta, {renderNoComments})
+      decodeB(rkNode)
+      createStr regs[ra]
+      regs[ra].node.strVal = renderTree(regs[rb].node, {renderNoComments})
     of opcQuit:
       if c.mode in {emRepl, emStaticExpr, emStaticStmt}:
         message(c.debug[pc], hintQuitCalled)
-        quit(int(getOrdValue(regs[ra])))
+        quit(int(getOrdValue(regs[ra].regToNode)))
       else:
-        return nil
+        return TFullReg(kind: rkNone)
     of opcSetLenStr:
-      decodeB(nkStrLit)
-      regs[ra].strVal.setLen(regs[rb].getOrdValue.int)
+      decodeB(rkNode)
+      createStrKeepNode regs[ra]
+      regs[ra].node.strVal.setLen(regs[rb].intVal.int)
     of opcOf:
-      decodeBC(nkIntLit)
+      decodeBC(rkInt)
       let typ = c.types[regs[rc].intVal.int]
-      regs[ra].intVal = ord(inheritanceDiff(regs[rb].typ, typ) >= 0)
+      regs[ra].intVal = ord(inheritanceDiff(regs[rb].node.typ, typ) >= 0)
     of opcIs:
-      decodeBC(nkIntLit)
-      let t1 = regs[rb].typ.skipTypes({tyTypeDesc})
+      decodeBC(rkInt)
+      let t1 = regs[rb].node.typ.skipTypes({tyTypeDesc})
       let t2 = c.types[regs[rc].intVal.int]
       # XXX: This should use the standard isOpImpl
       let match = if t2.kind == tyUserTypeClass: true
                   else: sameType(t1, t2)
       regs[ra].intVal = ord(match)
     of opcSetLenSeq:
-      decodeB(nkBracket)
-      let newLen = regs[rb].getOrdValue.int
-      setLen(regs[ra].sons, newLen)
-    of opcSwap, opcReset:
+      decodeB(rkNode)
+      let newLen = regs[rb].intVal.int
+      if regs[ra].node.isNil: stackTrace(c, tos, pc, errNilAccess)
+      else: setLen(regs[ra].node.sons, newLen)
+    of opcSwap:
+      let rb = instr.regB
+      if regs[ra].kind == regs[rb].kind:
+        case regs[ra].kind
+        of rkNone: discard
+        of rkInt: swap regs[ra].intVal, regs[rb].intVal
+        of rkFloat: swap regs[ra].floatVal, regs[rb].floatVal
+        of rkNode: swap regs[ra].node, regs[rb].node
+        of rkRegisterAddr: swap regs[ra].regAddr, regs[rb].regAddr
+        of rkNodeAddr: swap regs[ra].nodeAddr, regs[rb].nodeAddr
+      else:
+        internalError(c.debug[pc], "cannot swap operands")
+    of opcReset:
       internalError(c.debug[pc], "too implement")
+    of opcNarrowS:
+      decodeB(rkInt)
+      let min = -(1 shl (rb-1))
+      let max = (1 shl (rb-1))-1
+      if regs[ra].intVal < min or regs[ra].intVal > max:
+        stackTrace(c, tos, pc, errGenerated,
+          msgKindToString(errUnhandledExceptionX) % "value out of range")
+    of opcNarrowU:
+      decodeB(rkInt)
+      regs[ra].intVal = regs[ra].intVal and ((1'i64 shl rb)-1)
     of opcIsNil:
-      decodeB(nkIntLit)
-      regs[ra].intVal = ord(regs[rb].skipMeta.kind == nkNilLit)
+      decodeB(rkInt)
+      regs[ra].intVal = ord(regs[rb].node.kind == nkNilLit)
     of opcNBindSym:
-      decodeBx(nkMetaNode)
-      setMeta(regs[ra], copyTree(c.constants.sons[rbx]))
+      decodeBx(rkNode)
+      regs[ra].node = copyTree(c.constants.sons[rbx])
     of opcNChild:
-      decodeBC(nkMetaNode)
-      if regs[rb].kind != nkMetaNode:
-        internalError(c.debug[pc], "no MetaNode")
+      decodeBC(rkNode)
       let idx = regs[rc].intVal.int
-      let src = regs[rb].uast
+      let src = regs[rb].node
       if src.kind notin {nkEmpty..nkNilLit} and idx <% src.len:
-        setMeta(regs[ra], src.sons[idx])
+        regs[ra].node = src.sons[idx]
       else:
         stackTrace(c, tos, pc, errIndexOutOfBounds)
     of opcNSetChild:
-      decodeBC(nkMetaNode)
+      decodeBC(rkNode)
       let idx = regs[rb].intVal.int
-      var dest = regs[ra].uast
+      var dest = regs[ra].node
       if dest.kind notin {nkEmpty..nkNilLit} and idx <% dest.len:
-        dest.sons[idx] = regs[rc].uast
+        dest.sons[idx] = regs[rc].node
       else:
         stackTrace(c, tos, pc, errIndexOutOfBounds)
     of opcNAdd:
-      decodeBC(nkMetaNode)
-      var u = regs[rb].uast
-      u.add(regs[rc].uast)
-      setMeta(regs[ra], u)
+      decodeBC(rkNode)
+      var u = regs[rb].node
+      u.add(regs[rc].node)
+      regs[ra].node = u
     of opcNAddMultiple:
-      decodeBC(nkMetaNode)
-      let x = regs[rc]
-      var u = regs[rb].uast
+      decodeBC(rkNode)
+      let x = regs[rc].node
+      var u = regs[rb].node
       # XXX can be optimized:
-      for i in 0.. <x.len: u.add(x.sons[i].skipMeta)
-      setMeta(regs[ra], u)
+      for i in 0.. <x.len: u.add(x.sons[i])
+      regs[ra].node = u
     of opcNKind:
-      decodeB(nkIntLit)
-      regs[ra].intVal = ord(regs[rb].uast.kind)
+      decodeB(rkInt)
+      regs[ra].intVal = ord(regs[rb].node.kind)
     of opcNIntVal:
-      decodeB(nkIntLit)
-      let a = regs[rb].uast
+      decodeB(rkInt)
+      let a = regs[rb].node
       case a.kind
       of nkCharLit..nkInt64Lit: regs[ra].intVal = a.intVal
       else: stackTrace(c, tos, pc, errFieldXNotFound, "intVal")
     of opcNFloatVal:
-      decodeB(nkFloatLit)
-      let a = regs[rb].uast
+      decodeB(rkFloat)
+      let a = regs[rb].node
       case a.kind
       of nkFloatLit..nkFloat64Lit: regs[ra].floatVal = a.floatVal
       else: stackTrace(c, tos, pc, errFieldXNotFound, "floatVal")
     of opcNSymbol:
-      decodeB(nkSym)
-      let a = regs[rb].uast
+      decodeB(rkNode)
+      let a = regs[rb].node
       if a.kind == nkSym:
-        regs[ra].sym = a.sym
+        regs[ra].node = copyNode(a)
       else:
         stackTrace(c, tos, pc, errFieldXNotFound, "symbol")
     of opcNIdent:
-      decodeB(nkIdent)
-      let a = regs[rb].uast
+      decodeB(rkNode)
+      let a = regs[rb].node
       if a.kind == nkIdent:
-        regs[ra].ident = a.ident
+        regs[ra].node = copyNode(a)
       else:
         stackTrace(c, tos, pc, errFieldXNotFound, "ident")
     of opcNGetType:
       internalError(c.debug[pc], "unknown opcode " & $instr.opcode)
     of opcNStrVal:
-      decodeB(nkStrLit)
-      let a = regs[rb].uast
-      case a.kind
-      of nkStrLit..nkTripleStrLit: regs[ra].strVal = a.strVal
+      decodeB(rkNode)
+      createStr regs[ra]
+      let a = regs[rb].node
+      if a.kind in {nkStrLit..nkTripleStrLit}: regs[ra].node.strVal = a.strVal
       else: stackTrace(c, tos, pc, errFieldXNotFound, "strVal")
     of opcSlurp:
-      decodeB(nkStrLit)
-      regs[ra].strVal = opSlurp(regs[rb].strVal, c.debug[pc], c.module)
+      decodeB(rkNode)
+      createStr regs[ra]
+      regs[ra].node.strVal = opSlurp(regs[rb].node.strVal, c.debug[pc],
+                                     c.module)
     of opcGorge:
-      decodeBC(nkStrLit)
-      regs[ra].strVal = opGorge(regs[rb].strVal, regs[rc].strVal)
+      decodeBC(rkNode)
+      regs[ra].node.strVal = opGorge(regs[rb].node.strVal,
+                                     regs[rc].node.strVal)
     of opcNError:
-      stackTrace(c, tos, pc, errUser, regs[ra].strVal)
+      stackTrace(c, tos, pc, errUser, regs[ra].node.strVal)
     of opcNWarning:
-      message(c.debug[pc], warnUser, regs[ra].strVal)
+      message(c.debug[pc], warnUser, regs[ra].node.strVal)
     of opcNHint:
-      message(c.debug[pc], hintUser, regs[ra].strVal)
+      message(c.debug[pc], hintUser, regs[ra].node.strVal)
     of opcParseExprToAst:
-      decodeB(nkMetaNode)
+      decodeB(rkNode)
       # c.debug[pc].line.int - countLines(regs[rb].strVal) ?
-      let ast = parseString(regs[rb].strVal, c.debug[pc].toFilename,
+      let ast = parseString(regs[rb].node.strVal, c.debug[pc].toFilename,
                             c.debug[pc].line.int)
       if sonsLen(ast) != 1:
         globalError(c.debug[pc], errExprExpected, "multiple statements")
-      setMeta(regs[ra], ast.sons[0])
+      regs[ra].node = ast.sons[0]
     of opcParseStmtToAst:
-      decodeB(nkMetaNode)
-      let ast = parseString(regs[rb].strVal, c.debug[pc].toFilename,
+      decodeB(rkNode)
+      let ast = parseString(regs[rb].node.strVal, c.debug[pc].toFilename,
                             c.debug[pc].line.int)
-      setMeta(regs[ra], ast)
+      regs[ra].node = ast
     of opcCallSite:
-      ensureKind(nkMetaNode)
-      if c.callsite != nil: setMeta(regs[ra], c.callsite)
+      ensureKind(rkNode)
+      if c.callsite != nil: regs[ra].node = c.callsite
       else: stackTrace(c, tos, pc, errFieldXNotFound, "callsite")
     of opcNLineInfo:
-      decodeB(nkStrLit)
-      let n = regs[rb]
-      regs[ra].strVal = n.info.toFileLineCol
-      regs[ra].info = c.debug[pc]
+      decodeB(rkNode)
+      let n = regs[rb].node
+      createStr regs[ra]
+      regs[ra].node.strVal = n.info.toFileLineCol
+      regs[ra].node.info = c.debug[pc]
     of opcEqIdent:
-      decodeBC(nkIntLit)
-      if regs[rb].kind == nkIdent and regs[rc].kind == nkIdent:
-        regs[ra].intVal = ord(regs[rb].ident.id == regs[rc].ident.id)
+      decodeBC(rkInt)
+      if regs[rb].node.kind == nkIdent and regs[rc].node.kind == nkIdent:
+        regs[ra].intVal = ord(regs[rb].node.ident.id == regs[rc].node.ident.id)
       else:
         regs[ra].intVal = 0
     of opcStrToIdent:
-      decodeB(nkIdent)
-      if regs[rb].kind notin {nkStrLit..nkTripleStrLit}:
+      decodeB(rkNode)
+      if regs[rb].node.kind notin {nkStrLit..nkTripleStrLit}:
         stackTrace(c, tos, pc, errFieldXNotFound, "strVal")
       else:
-        regs[ra].info = c.debug[pc]
-        regs[ra].ident = getIdent(regs[rb].strVal)
+        regs[ra].node = newNodeI(nkIdent, c.debug[pc])
+        regs[ra].node.ident = getIdent(regs[rb].node.strVal)
     of opcIdentToStr:
-      decodeB(nkStrLit)
-      let a = regs[rb]
-      regs[ra].info = c.debug[pc]
+      decodeB(rkNode)
+      let a = regs[rb].node
+      createStr regs[ra]
+      regs[ra].node.info = c.debug[pc]
       if a.kind == nkSym:
-        regs[ra].strVal = a.sym.name.s
+        regs[ra].node.strVal = a.sym.name.s
       elif a.kind == nkIdent:
-        regs[ra].strVal = a.ident.s
+        regs[ra].node.strVal = a.ident.s
       else:
         stackTrace(c, tos, pc, errFieldXNotFound, "ident")
     of opcSetType:
-      regs[ra].typ = c.types[instr.regBx - wordExcess]
+      if regs[ra].kind != rkNode:
+        internalError(c.debug[pc], "cannot set type")
+      regs[ra].node.typ = c.types[instr.regBx - wordExcess]
     of opcConv:
       let rb = instr.regB
       inc pc
-      let typ = c.types[c.code[pc].regBx - wordExcess]
-      if opConv(regs[ra], regs[rb], typ):
+      let desttyp = c.types[c.code[pc].regBx - wordExcess]
+      inc pc
+      let srctyp = c.types[c.code[pc].regBx - wordExcess]
+
+      if opConv(regs[ra], regs[rb], desttyp, srctyp):
         stackTrace(c, tos, pc, errGenerated,
           msgKindToString(errIllegalConvFromXtoY) % [
-          "unknown type" , "unknown type"])
+          typeToString(srctyp), typeToString(desttyp)])
     of opcCast:
       let rb = instr.regB
       inc pc
-      let typ = c.types[c.code[pc].regBx - wordExcess]
+      let desttyp = c.types[c.code[pc].regBx - wordExcess]
+      inc pc
+      let srctyp = c.types[c.code[pc].regBx - wordExcess]
+
       when hasFFI:
-        let dest = fficast(regs[rb], typ)
+        let dest = fficast(regs[rb], desttyp)
         asgnRef(regs[ra], dest)
       else:
         globalError(c.debug[pc], "cannot evaluate cast")
     of opcNSetIntVal:
-      decodeB(nkMetaNode)
-      var dest = regs[ra].uast
+      decodeB(rkNode)
+      var dest = regs[ra].node
       if dest.kind in {nkCharLit..nkInt64Lit} and 
-         regs[rb].kind in {nkCharLit..nkInt64Lit}:
+         regs[rb].kind in {rkInt}:
         dest.intVal = regs[rb].intVal
       else:
         stackTrace(c, tos, pc, errFieldXNotFound, "intVal")
     of opcNSetFloatVal:
-      decodeB(nkMetaNode)
-      var dest = regs[ra].uast
+      decodeB(rkNode)
+      var dest = regs[ra].node
       if dest.kind in {nkFloatLit..nkFloat64Lit} and 
-         regs[rb].kind in {nkFloatLit..nkFloat64Lit}:
+         regs[rb].kind in {rkFloat}:
         dest.floatVal = regs[rb].floatVal
       else: 
         stackTrace(c, tos, pc, errFieldXNotFound, "floatVal")
     of opcNSetSymbol:
-      decodeB(nkMetaNode)
-      var dest = regs[ra].uast
-      if dest.kind == nkSym and regs[rb].kind == nkSym:
-        dest.sym = regs[rb].sym
+      decodeB(rkNode)
+      var dest = regs[ra].node
+      if dest.kind == nkSym and regs[rb].node.kind == nkSym:
+        dest.sym = regs[rb].node.sym
       else: 
         stackTrace(c, tos, pc, errFieldXNotFound, "symbol")
     of opcNSetIdent:
-      decodeB(nkMetaNode)
-      var dest = regs[ra].uast
-      if dest.kind == nkIdent and regs[rb].kind == nkIdent:
-        dest.ident = regs[rb].ident
+      decodeB(rkNode)
+      var dest = regs[ra].node
+      if dest.kind == nkIdent and regs[rb].node.kind == nkIdent:
+        dest.ident = regs[rb].node.ident
       else: 
         stackTrace(c, tos, pc, errFieldXNotFound, "ident")
     of opcNSetType:
-      decodeB(nkMetaNode)
-      let b = regs[rb].skipMeta
+      decodeB(rkNode)
+      let b = regs[rb].node
       internalAssert b.kind == nkSym and b.sym.kind == skType
-      regs[ra].uast.typ = b.sym.typ
+      internalAssert regs[ra].node != nil
+      regs[ra].node.typ = b.sym.typ
     of opcNSetStrVal:
-      decodeB(nkMetaNode)
-      var dest = regs[ra].uast
+      decodeB(rkNode)
+      var dest = regs[ra].node
       if dest.kind in {nkStrLit..nkTripleStrLit} and 
-         regs[rb].kind in {nkStrLit..nkTripleStrLit}:
-        dest.strVal = regs[rb].strVal
+         regs[rb].kind in {rkNode}:
+        dest.strVal = regs[rb].node.strVal
       else:
         stackTrace(c, tos, pc, errFieldXNotFound, "strVal")
     of opcNNewNimNode:
-      decodeBC(nkMetaNode)
+      decodeBC(rkNode)
       var k = regs[rb].intVal
-      if k < 0 or k > ord(high(TNodeKind)) or k == ord(nkMetaNode):
+      if k < 0 or k > ord(high(TNodeKind)):
         internalError(c.debug[pc],
           "request to create a NimNode of invalid kind")
-      let cc = regs[rc].skipMeta
-      setMeta(regs[ra], newNodeI(TNodeKind(int(k)), 
-        if cc.kind == nkNilLit: c.debug[pc] else: cc.info))
-      regs[ra].sons[0].flags.incl nfIsRef
+      let cc = regs[rc].node
+      regs[ra].node = newNodeI(TNodeKind(int(k)),
+        if cc.kind == nkNilLit: c.debug[pc] else: cc.info)
+      regs[ra].node.flags.incl nfIsRef
     of opcNCopyNimNode:
-      decodeB(nkMetaNode)
-      setMeta(regs[ra], copyNode(regs[rb]))
+      decodeB(rkNode)
+      regs[ra].node = copyNode(regs[rb].node)
     of opcNCopyNimTree:
-      decodeB(nkMetaNode)
-      setMeta(regs[ra], copyTree(regs[rb]))
+      decodeB(rkNode)
+      regs[ra].node = copyTree(regs[rb].node)
     of opcNDel:
-      decodeBC(nkMetaNode)
+      decodeBC(rkNode)
       let bb = regs[rb].intVal.int
       for i in countup(0, regs[rc].intVal.int-1):
-        delSon(regs[ra].uast, bb)
+        delSon(regs[ra].node, bb)
     of opcGenSym:
-      decodeBC(nkMetaNode)
+      decodeBC(rkNode)
       let k = regs[rb].intVal
-      let name = if regs[rc].strVal.len == 0: ":tmp" else: regs[rc].strVal
+      let name = if regs[rc].node.strVal.len == 0: ":tmp"
+                 else: regs[rc].node.strVal
       if k < 0 or k > ord(high(TSymKind)):
         internalError(c.debug[pc], "request to create symbol of invalid kind")
       var sym = newSym(k.TSymKind, name.getIdent, c.module, c.debug[pc])
       incl(sym.flags, sfGenSym)
-      setMeta(regs[ra], newSymNode(sym))
+      regs[ra].node = newSymNode(sym)
     of opcTypeTrait:
       # XXX only supports 'name' for now; we can use regC to encode the
       # type trait operation
-      decodeB(nkStrLit)
-      var typ = regs[rb].typ
+      decodeB(rkNode)
+      var typ = regs[rb].node.typ
       internalAssert typ != nil
       while typ.kind == tyTypeDesc and typ.len > 0: typ = typ.sons[0]
-      regs[ra].strVal = typ.typeToString(preferExported)
-    of opcGlobalOnce:
-      let rb = instr.regBx
-      if c.globals.sons[rb - wordExcess - 1].kind != nkEmpty:
-        # skip initialization instructions:
-        while true:
-          inc pc
-          if c.code[pc].opcode in {opcWrGlobal, opcWrGlobalRef} and
-             c.code[pc].regBx == rb:
-            break
-    of opcGlobalAlias:
-      let rb = instr.regBx - wordExcess - 1
-      regs[ra] = c.globals.sons[rb]
+      createStr regs[ra]
+      regs[ra].node.strVal = typ.typeToString(preferExported)
     inc pc
 
-proc fixType(result, n: PNode) {.inline.} =
-  # XXX do it deeply for complex values; there seems to be no simple
-  # solution except to check it deeply here.
-  #if result.typ.isNil: result.typ = n.typ
-  discard
-
 proc execute(c: PCtx, start: int): PNode =
   var tos = PStackFrame(prc: nil, comesFrom: 0, next: nil)
   newSeq(tos.slots, c.prc.maxSlots)
-  for i in 0 .. <c.prc.maxSlots: tos.slots[i] = newNode(nkEmpty)
-  result = rawExecute(c, start, tos)
+  result = rawExecute(c, start, tos).regToNode
 
 proc evalStmt*(c: PCtx, n: PNode) =
   let n = transformExpr(c.module, n)
@@ -1090,9 +1225,6 @@ proc evalExpr*(c: PCtx, n: PNode): PNode =
   let start = genExpr(c, n)
   assert c.code[start].opcode != opcEof
   result = execute(c, start)
-  if not result.isNil:
-    result = result.skipMeta
-    fixType(result, n)
 
 # for now we share the 'globals' environment. XXX Coming soon: An API for
 # storing&loading the 'globals' environment to get what a component system
@@ -1136,11 +1268,11 @@ proc evalConstExprAux(module, prc: PSym, n: PNode, mode: TEvalMode): PNode =
   let start = genExpr(c, n, requiresValue = mode!=emStaticStmt)
   if c.code[start].opcode == opcEof: return emptyNode
   assert c.code[start].opcode != opcEof
+  when debugEchoCode: c.echoCode start
   var tos = PStackFrame(prc: prc, comesFrom: 0, next: nil)
   newSeq(tos.slots, c.prc.maxSlots)
-  for i in 0 .. <c.prc.maxSlots: tos.slots[i] = newNode(nkEmpty)
-  result = rawExecute(c, start, tos)
-  fixType(result, n)
+  #for i in 0 .. <c.prc.maxSlots: tos.slots[i] = newNode(nkEmpty)
+  result = rawExecute(c, start, tos).regToNode
 
 proc evalConstExpr*(module: PSym, e: PNode): PNode = 
   result = evalConstExprAux(module, nil, e, emConst)
@@ -1151,13 +1283,14 @@ proc evalStaticExpr*(module: PSym, e: PNode, prc: PSym): PNode =
 proc evalStaticStmt*(module: PSym, e: PNode, prc: PSym) =
   discard evalConstExprAux(module, prc, e, emStaticStmt)
 
+proc setupCompileTimeVar*(module: PSym, n: PNode) =
+  discard evalConstExprAux(module, nil, n, emStaticStmt)
+
 proc setupMacroParam(x: PNode): PNode =
   result = x
   if result.kind in {nkHiddenSubConv, nkHiddenStdConv}: result = result.sons[1]
-  let y = result
-  y.flags.incl nfIsRef
-  result = newNode(nkMetaNode)
-  result.add y
+  result = canonValue(result)
+  result.flags.incl nfIsRef
   result.typ = x.typ
 
 var evalMacroCounter: int
@@ -1183,15 +1316,16 @@ proc evalMacroCall*(module: PSym, n, nOrig: PNode, sym: PSym): PNode =
   # doesn't end up in the parameter:
   #InternalAssert tos.slots.len >= L
   # return value:
-  tos.slots[0] = newNodeIT(nkEmpty, n.info, sym.typ.sons[0])
+  tos.slots[0].kind = rkNode
+  tos.slots[0].node = newNodeIT(nkEmpty, n.info, sym.typ.sons[0])
   # setup parameters:
   for i in 1 .. < min(tos.slots.len, L):
-    tos.slots[i] = setupMacroParam(n.sons[i])
+    tos.slots[i].kind = rkNode
+    tos.slots[i].node = setupMacroParam(n.sons[i])
   # temporary storage:
-  for i in L .. <maxSlots: tos.slots[i] = newNode(nkEmpty)
-  result = rawExecute(c, start, tos)
+  #for i in L .. <maxSlots: tos.slots[i] = newNode(nkEmpty)
+  result = rawExecute(c, start, tos).regToNode
   if cyclicTree(result): globalError(n.info, errCyclicTree)
   dec(evalMacroCounter)
-  if result != nil:
-    result = result.skipMeta
   c.callsite = nil
+  #debug result
diff --git a/compiler/vmdef.nim b/compiler/vmdef.nim
index 87159c813..d0c38a2ad 100644
--- a/compiler/vmdef.nim
+++ b/compiler/vmdef.nim
@@ -8,7 +8,7 @@
 #
 
 ## This module contains the type definitions for the new evaluation engine.
-## An instruction is 1-2 int32s in memory, it is a register based VM.
+## An instruction is 1-3 int32s in memory, it is a register based VM.
 
 import ast, passes, msgs, intsets
 
@@ -16,6 +16,9 @@ const
   byteExcess* = 128 # we use excess-K for immediates
   wordExcess* = 32768
 
+  MaxLoopIterations* = 500_000 # max iterations of all loops
+
+
 type
   TRegister* = range[0..255]
   TDest* = range[-1 .. 255]
@@ -32,17 +35,17 @@ type
     opcAsgnFloat,
     opcAsgnRef,
     opcAsgnComplex,
+    opcRegToNode,
+    opcNodeToReg,
 
     opcLdArr,  # a = b[c]
-    opcLdArrRef,
     opcWrArr,  # a[b] = c
-    opcWrArrRef,
     opcLdObj,  # a = b.c
-    opcLdObjRef,
     opcWrObj,  # a.b = c
-    opcWrObjRef,
-    opcAddr,
-    opcDeref,
+    opcAddrReg,
+    opcAddrNode,
+    opcLdDeref,
+    opcWrDeref,
     opcWrStrIdx,
     opcLdStrIdx, # a = b[c]
     
@@ -64,6 +67,7 @@ type
     opcContainsSet, opcRepr, opcSetLenStr, opcSetLenSeq,
     opcSwap, opcIsNil, opcOf, opcIs,
     opcSubStr, opcConv, opcCast, opcQuit, opcReset,
+    opcNarrowS, opcNarrowU,
     
     opcAddStrCh,
     opcAddStrStr,
@@ -109,6 +113,7 @@ type
     opcTJmp,  # jump Bx if A != 0
     opcFJmp,  # jump Bx if A == 0
     opcJmp,   # jump Bx
+    opcJmpBack, # jump Bx; resulting from a while loop
     opcBranch,  # branch for 'case'
     opcTry,
     opcExcept,
@@ -117,15 +122,14 @@ type
     opcNew,
     opcNewSeq,
     opcLdNull,    # dest = nullvalue(types[Bx])
+    opcLdNullReg,
     opcLdConst,   # dest = constants[Bx]
     opcAsgnConst, # dest = copy(constants[Bx])
     opcLdGlobal,  # dest = globals[Bx]
+    opcLdGlobalAddr, # dest = addr(globals[Bx])
+
     opcLdImmInt,  # dest = immediate value
     opcNBindSym,
-    opcWrGlobal,
-    opcWrGlobalRef,
-    opcGlobalAlias, # load an alias to a global into a register
-    opcGlobalOnce,  # used to introduce an assignment to a global once
     opcSetType,   # dest.typ = types[Bx]
     opcTypeTrait
 
@@ -159,14 +163,13 @@ type
     slotTempInt,      # some temporary int
     slotTempFloat,    # some temporary float
     slotTempStr,      # some temporary string
-    slotTempComplex   # some complex temporary (n.sons field is used)
+    slotTempComplex   # some complex temporary (s.node field is used)
 
   PProc* = ref object
     blocks*: seq[TBlock]    # blocks; temp data structure
+    sym*: PSym
     slots*: array[TRegister, tuple[inUse: bool, kind: TSlotKind]]
     maxSlots*: int
-    globals*: array[TRegister, int] # hack: to support passing globals byref
-                                    # we map a slot persistently to a global
     
   PCtx* = ref TCtx
   TCtx* = object of passes.TPassContext # code gen context
@@ -183,6 +186,8 @@ type
     callsite*: PNode
     mode*: TEvalMode
     features*: TSandboxFlags
+    traceActive*: bool
+    loopIterations*: int
 
   TPosition* = distinct int
 
@@ -191,7 +196,7 @@ type
 proc newCtx*(module: PSym): PCtx =
   PCtx(code: @[], debug: @[],
     globals: newNode(nkStmtListExpr), constants: newNode(nkStmtList), types: @[],
-    prc: PProc(blocks: @[]), module: module)
+    prc: PProc(blocks: @[]), module: module, loopIterations: MaxLoopIterations)
 
 proc refresh*(c: PCtx, module: PSym) =
   c.module = module
diff --git a/compiler/vmgen.nim b/compiler/vmgen.nim
index a6d044e24..3c0f8dbc9 100644
--- a/compiler/vmgen.nim
+++ b/compiler/vmgen.nim
@@ -11,7 +11,7 @@
 
 import
   unsigned, strutils, ast, astalgo, types, msgs, renderer, vmdef, 
-  trees, intsets, rodread, magicsys, options
+  trees, intsets, rodread, magicsys, options, lowerings
 
 from os import splitFile
 
@@ -41,7 +41,14 @@ proc codeListing(c: PCtx, result: var string, start=0) =
     let x = c.code[i]
 
     let opc = opcode(x)
-    if opc < firstABxInstr:
+    if opc in {opcConv, opcCast}:
+      let y = c.code[i+1]
+      let z = c.code[i+2]
+      result.addf("\t$#\tr$#, r$#, $#, $#", ($opc).substr(3), x.regA, x.regB,
+        c.types[y.regBx-wordExcess].typeToString, 
+        c.types[z.regBx-wordExcess].typeToString)
+      inc i, 2
+    elif opc < firstABxInstr:
       result.addf("\t$#\tr$#, r$#, r$#", ($opc).substr(3), x.regA, 
                   x.regB, x.regC)
     elif opc in relativeJumps:
@@ -92,10 +99,10 @@ proc genLabel(c: PCtx): TPosition =
   result = TPosition(c.code.len)
   #c.jumpTargets.incl(c.code.len)
 
-proc jmpBack(c: PCtx, n: PNode, opc: TOpcode, p = TPosition(0)) =
+proc jmpBack(c: PCtx, n: PNode, p = TPosition(0)) =
   let dist = p.int - c.code.len
   internalAssert(-0x7fff < dist and dist < 0x7fff)
-  gABx(c, n, opc, 0, dist)
+  gABx(c, n, opcJmpBack, 0, dist)
 
 proc patch(c: PCtx, p: TPosition) =
   # patch with current index
@@ -139,25 +146,12 @@ proc getTemp(c: PCtx; typ: PType): TRegister =
       if not c.slots[i].inUse:
         c.slots[i] = (inUse: true, kind: k)
         return TRegister(i)
+  if c.maxSlots >= high(TRegister):
+    internalError("cannot generate code; too many registers required")
   result = TRegister(c.maxSlots)
   c.slots[c.maxSlots] = (inUse: true, kind: k)
   inc c.maxSlots
 
-proc getGlobalSlot(c: PCtx; n: PNode; s: PSym): TRegister =
-  let p = c.prc
-  for i in 0 .. p.maxSlots-1:
-    if p.globals[i] == s.id: return TRegister(i)
-
-  result = TRegister(p.maxSlots)
-  p.slots[p.maxSlots] = (inUse: true, kind: slotFixedVar)
-  p.globals[p.maxSlots] = s.id
-  inc p.maxSlots
-  # XXX this is still not correct! We need to load the global in a proc init
-  # section, otherwise control flow could lead to a usage before it's been
-  # loaded.
-  c.gABx(n, opcGlobalAlias, result, s.position)
-  # XXX add some internal asserts here
-
 proc freeTemp(c: PCtx; r: TRegister) =
   let c = c.prc
   if c.slots[r].kind >= slotSomeTemp: c.slots[r].inUse = false
@@ -242,20 +236,20 @@ proc genWhile(c: PCtx; n: PNode) =
   withBlock(nil):
     if isTrue(n.sons[0]):
       c.gen(n.sons[1])
-      c.jmpBack(n, opcJmp, L1)
+      c.jmpBack(n, L1)
     elif isNotOpr(n.sons[0]):
       var tmp = c.genx(n.sons[0].sons[1])
       let L2 = c.xjmp(n, opcTJmp, tmp)
       c.freeTemp(tmp)
       c.gen(n.sons[1])
-      c.jmpBack(n, opcJmp, L1)
+      c.jmpBack(n, L1)
       c.patch(L2)
     else:
       var tmp = c.genx(n.sons[0])
       let L2 = c.xjmp(n, opcFJmp, tmp)
       c.freeTemp(tmp)
       c.gen(n.sons[1])
-      c.jmpBack(n, opcJmp, L1)
+      c.jmpBack(n, L1)
       c.patch(L2)
 
 proc genBlock(c: PCtx; n: PNode; dest: var TDest) =
@@ -321,9 +315,20 @@ proc genAndOr(c: PCtx; n: PNode; opc: TOpcode; dest: var TDest) =
   c.gen(n.sons[2], dest)
   c.patch(L1)
 
+proc canonValue*(n: PNode): PNode =
+  if n.kind == nkExprColonExpr:
+    result = n.sons[1]
+  elif n.hasSubnodeWith(nkExprColonExpr):
+    result = n.copyNode
+    newSeq(result.sons, n.len)
+    for i in 0.. <n.len:
+      result.sons[i] = canonValue(n.sons[i])
+  else:
+    result = n
+
 proc rawGenLiteral(c: PCtx; n: PNode): int =
   result = c.constants.len
-  c.constants.add n
+  c.constants.add n.canonValue
   internalAssert result < 0x7fff
 
 proc sameConstant*(a, b: PNode): bool =
@@ -339,10 +344,10 @@ proc sameConstant*(a, b: PNode): bool =
     of nkStrLit..nkTripleStrLit: result = a.strVal == b.strVal
     of nkType: result = a.typ == b.typ
     of nkEmpty, nkNilLit: result = true
-    else: 
-      if sonsLen(a) == sonsLen(b): 
-        for i in countup(0, sonsLen(a) - 1): 
-          if not sameConstant(a.sons[i], b.sons[i]): return 
+    else:
+      if sonsLen(a) == sonsLen(b):
+        for i in countup(0, sonsLen(a) - 1):
+          if not sameConstant(a.sons[i], b.sons[i]): return
         result = true
 
 proc genLiteral(c: PCtx; n: PNode): int =
@@ -461,21 +466,45 @@ proc genCall(c: PCtx; n: PNode; dest: var TDest) =
     c.gABC(n, opcIndCallAsgn, dest, x, n.len)
   c.freeTempRange(x, n.len)
 
+template isGlobal(s: PSym): bool = sfGlobal in s.flags and s.kind != skForVar
+
 proc needsAsgnPatch(n: PNode): bool = 
-  n.kind in {nkBracketExpr, nkDotExpr, nkCheckedFieldExpr}
+  n.kind in {nkBracketExpr, nkDotExpr, nkCheckedFieldExpr,
+             nkDerefExpr, nkHiddenDeref} or (n.kind == nkSym and n.sym.isGlobal)
+
+proc genField(n: PNode): TRegister =
+  if n.kind != nkSym or n.sym.kind != skField:
+    internalError(n.info, "no field symbol")
+  let s = n.sym
+  if s.position > high(result):
+      internalError(n.info,
+        "too large offset! cannot generate code for: " & s.name.s)
+  result = s.position
 
 proc genAsgnPatch(c: PCtx; le: PNode, value: TRegister) =
   case le.kind
   of nkBracketExpr:
-    let dest = c.genx(le.sons[0])
+    let dest = c.genx(le.sons[0], {gfAddrOf})
     let idx = c.genx(le.sons[1])
-    c.gABC(le, opcWrArrRef, dest, idx, value)
+    c.gABC(le, opcWrArr, dest, idx, value)
+    c.freeTemp(dest)
+    c.freeTemp(idx)
   of nkDotExpr, nkCheckedFieldExpr:
     # XXX field checks here
     let left = if le.kind == nkDotExpr: le else: le.sons[0]
-    let dest = c.genx(left.sons[0])
-    let idx = c.genx(left.sons[1])
-    c.gABC(left, opcWrObjRef, dest, idx, value)
+    let dest = c.genx(left.sons[0], {gfAddrOf})
+    let idx = genField(left.sons[1])
+    c.gABC(left, opcWrObj, dest, idx, value)
+    c.freeTemp(dest)
+  of nkDerefExpr, nkHiddenDeref:
+    let dest = c.genx(le.sons[0], {gfAddrOf})
+    c.gABC(le, opcWrDeref, dest, value)
+    c.freeTemp(dest)
+  of nkSym:
+    if le.sym.isGlobal:
+      let dest = c.genx(le, {gfAddrOf})
+      c.gABC(le, opcWrDeref, dest, value)
+      c.freeTemp(dest)
   else:
     discard
 
@@ -521,6 +550,30 @@ proc genBinaryABC(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode) =
   c.freeTemp(tmp)
   c.freeTemp(tmp2)
 
+proc genNarrow(c: PCtx; n: PNode; dest: TDest) =
+  let t = skipTypes(n.typ, abstractVar-{tyTypeDesc})
+  # uint is uint64 in the VM, we we only need to mask the result for
+  # other unsigned types:
+  if t.kind in {tyUInt8..tyUInt32}:
+    c.gABC(n, opcNarrowU, dest, TRegister(t.size*8))
+  elif t.kind in {tyInt8..tyInt32}:
+    c.gABC(n, opcNarrowS, dest, TRegister(t.size*8))
+
+proc genNarrowU(c: PCtx; n: PNode; dest: TDest) =
+  let t = skipTypes(n.typ, abstractVar-{tyTypeDesc})
+  # uint is uint64 in the VM, we we only need to mask the result for
+  # other unsigned types:
+  if t.kind in {tyUInt8..tyUInt32, tyInt8..tyInt32}:
+    c.gABC(n, opcNarrowU, dest, TRegister(t.size*8))
+
+proc genBinaryABCnarrow(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode) =
+  genBinaryABC(c, n, dest, opc)
+  genNarrow(c, n, dest)
+
+proc genBinaryABCnarrowU(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode) =
+  genBinaryABC(c, n, dest, opc)
+  genNarrowU(c, n, dest)
+
 proc genSetType(c: PCtx; n: PNode; dest: TRegister) =
   let t = skipTypes(n.typ, abstractInst-{tyTypeDesc})
   if t.kind == tySet:
@@ -582,13 +635,14 @@ proc genAddSubInt(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode) =
     c.freeTemp(tmp)
   else:
     genBinaryABC(c, n, dest, opc)
+  c.genNarrow(n, dest)
 
 proc genConv(c: PCtx; n, arg: PNode; dest: var TDest; opc=opcConv) =  
   let tmp = c.genx(arg)
-  c.gABx(n, opcSetType, tmp, genType(c, arg.typ))
   if dest < 0: dest = c.getTemp(n.typ)
   c.gABC(n, opc, dest, tmp)
   c.gABx(n, opc, 0, genType(c, n.typ))
+  c.gABx(n, opc, 0, genType(c, arg.typ))
   c.freeTemp(tmp)
 
 proc genCard(c: PCtx; n: PNode; dest: var TDest) =
@@ -614,10 +668,17 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest) =
     c.genAddSubInt(n, dest, opcAddInt)
   of mInc, mDec:
     unused(n, dest)
-    var d = c.genx(n.sons[1]).TDest
-    c.genAddSubInt(n, d, if m == mInc: opcAddInt else: opcSubInt)
+    let opc = if m == mInc: opcAddInt else: opcSubInt
+    let d = c.genx(n.sons[1])
+    if n.sons[2].isInt8Lit:
+      c.gABI(n, succ(opc), d, d, n.sons[2].intVal)
+    else:
+      let tmp = c.genx(n.sons[2])
+      c.gABC(n, opc, d, d, tmp)
+      c.freeTemp(tmp)
+    c.genNarrow(n.sons[1], d)
     c.genAsgnPatch(n.sons[1], d)
-    c.freeTemp(d.TRegister)
+    c.freeTemp(d)
   of mOrd, mChr, mArrToSeq: c.gen(n.sons[1], dest)
   of mNew, mNewFinalize:
     unused(n, dest)
@@ -627,6 +688,7 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest) =
     c.genNewSeq(n)
   of mNewString:
     genUnaryABC(c, n, dest, opcNewStr)
+    # XXX buggy
   of mNewStringOfCap:
     # we ignore the 'cap' argument and translate it as 'newString(0)'.
     # eval n.sons[1] for possible side effects:
@@ -635,6 +697,7 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest) =
     if dest < 0: dest = c.getTemp(n.typ)
     c.gABC(n, opcNewStr, dest, tmp)
     c.freeTemp(tmp)
+    # XXX buggy
   of mLengthOpenArray, mLengthArray, mLengthSeq:
     genUnaryABI(c, n, dest, opcLenSeq)
   of mLengthStr:
@@ -648,23 +711,23 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest) =
     c.freeTemp(d)
     c.freeTemp(tmp)
   of mCard: genCard(c, n, dest)
-  of mMulI, mMulI64: genBinaryABC(c, n, dest, opcMulInt)
-  of mDivI, mDivI64: genBinaryABC(c, n, dest, opcDivInt)
-  of mModI, mModI64: genBinaryABC(c, n, dest, opcModInt)
+  of mMulI, mMulI64: genBinaryABCnarrow(c, n, dest, opcMulInt)
+  of mDivI, mDivI64: genBinaryABCnarrow(c, n, dest, opcDivInt)
+  of mModI, mModI64: genBinaryABCnarrow(c, n, dest, opcModInt)
   of mAddF64: genBinaryABC(c, n, dest, opcAddFloat)
   of mSubF64: genBinaryABC(c, n, dest, opcSubFloat)
   of mMulF64: genBinaryABC(c, n, dest, opcMulFloat)
   of mDivF64: genBinaryABC(c, n, dest, opcDivFloat)
-  of mShrI, mShrI64: genBinaryABC(c, n, dest, opcShrInt)
-  of mShlI, mShlI64: genBinaryABC(c, n, dest, opcShlInt)
-  of mBitandI, mBitandI64: genBinaryABC(c, n, dest, opcBitandInt)
-  of mBitorI, mBitorI64: genBinaryABC(c, n, dest, opcBitorInt)
-  of mBitxorI, mBitxorI64: genBinaryABC(c, n, dest, opcBitxorInt)
-  of mAddU: genBinaryABC(c, n, dest, opcAddu)
-  of mSubU: genBinaryABC(c, n, dest, opcSubu)
-  of mMulU: genBinaryABC(c, n, dest, opcMulu)
-  of mDivU: genBinaryABC(c, n, dest, opcDivu)
-  of mModU: genBinaryABC(c, n, dest, opcModu)
+  of mShrI, mShrI64: genBinaryABCnarrowU(c, n, dest, opcShrInt)
+  of mShlI, mShlI64: genBinaryABCnarrowU(c, n, dest, opcShlInt)
+  of mBitandI, mBitandI64: genBinaryABCnarrowU(c, n, dest, opcBitandInt)
+  of mBitorI, mBitorI64: genBinaryABCnarrowU(c, n, dest, opcBitorInt)
+  of mBitxorI, mBitxorI64: genBinaryABCnarrowU(c, n, dest, opcBitxorInt)
+  of mAddU: genBinaryABCnarrowU(c, n, dest, opcAddu)
+  of mSubU: genBinaryABCnarrowU(c, n, dest, opcSubu)
+  of mMulU: genBinaryABCnarrowU(c, n, dest, opcMulu)
+  of mDivU: genBinaryABCnarrowU(c, n, dest, opcDivu)
+  of mModU: genBinaryABCnarrowU(c, n, dest, opcModu)
   of mEqI, mEqI64, mEqB, mEqEnum, mEqCh:
     genBinaryABC(c, n, dest, opcEqInt)
   of mLeI, mLeI64, mLeEnum, mLeCh, mLeB:
@@ -678,12 +741,16 @@ proc genMagic(c: PCtx; n: PNode; dest: var TDest) =
   of mLtPtr, mLtU, mLtU64: genBinaryABC(c, n, dest, opcLtu)
   of mEqProc, mEqRef, mEqUntracedRef, mEqCString:
     genBinaryABC(c, n, dest, opcEqRef)
-  of mXor: genBinaryABC(c, n, dest, opcXor)
+  of mXor: genBinaryABCnarrowU(c, n, dest, opcXor)
   of mNot: genUnaryABC(c, n, dest, opcNot)
-  of mUnaryMinusI, mUnaryMinusI64: genUnaryABC(c, n, dest, opcUnaryMinusInt)
+  of mUnaryMinusI, mUnaryMinusI64:
+    genUnaryABC(c, n, dest, opcUnaryMinusInt)
+    genNarrow(c, n, dest)
   of mUnaryMinusF64: genUnaryABC(c, n, dest, opcUnaryMinusFloat)
   of mUnaryPlusI, mUnaryPlusI64, mUnaryPlusF64: gen(c, n.sons[1], dest)
-  of mBitnotI, mBitnotI64: genUnaryABC(c, n, dest, opcBitnotInt)
+  of mBitnotI, mBitnotI64: 
+    genUnaryABC(c, n, dest, opcBitnotInt)
+    genNarrowU(c, n, dest)
   of mZe8ToI, mZe8ToI64, mZe16ToI, mZe16ToI64, mZe32ToI64, mZeIToI64,
      mToU8, mToU16, mToU32, mToFloat, mToBiggestFloat, mToInt, 
      mToBiggestInt, mCharToStr, mBoolToStr, mIntToStr, mInt64ToStr, 
@@ -896,6 +963,10 @@ const
     tyFloat, tyFloat32, tyFloat64, tyFloat128,
     tyUInt, tyUInt8, tyUInt16, tyUInt32, tyUInt64}
 
+proc fitsRegister*(t: PType): bool =
+  t.skipTypes(abstractInst-{tyTypeDesc}).kind in {
+    tyRange, tyEnum, tyBool, tyInt..tyUInt64}
+
 proc requiresCopy(n: PNode): bool =
   if n.typ.skipTypes(abstractInst-{tyTypeDesc}).kind in atomicTypes:
     result = false
@@ -907,22 +978,33 @@ proc requiresCopy(n: PNode): bool =
 proc unneededIndirection(n: PNode): bool =
   n.typ.skipTypes(abstractInst-{tyTypeDesc}).kind == tyRef
 
-proc skipDeref(n: PNode): PNode =
-  if n.kind in {nkDerefExpr, nkHiddenDeref} and unneededIndirection(n.sons[0]):
-    result = n.sons[0]
-  else:
-    result = n
-
 proc genAddrDeref(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode;
                   flags: TGenFlags) = 
   # a nop for certain types
-  let flags = if opc == opcAddr: flags+{gfAddrOf} else: flags
-  if unneededIndirection(n.sons[0]):
-    gen(c, n.sons[0], dest, flags)
+  let isAddr = opc in {opcAddrNode, opcAddrReg}
+  let newflags = if isAddr: flags+{gfAddrOf} else: flags
+  # consider:
+  # proc foo(f: var ref int) =
+  #   f = new(int)
+  # proc blah() =
+  #   var x: ref int
+  #   foo x
+  #
+  # The type of 'f' is 'var ref int' and of 'x' is 'ref int'. Hence for
+  # nkAddr we must not use 'unneededIndirection', but for deref we use it.
+  if not isAddr and unneededIndirection(n.sons[0]):
+    gen(c, n.sons[0], dest, newflags)
   else:
-    let tmp = c.genx(n.sons[0], flags)
+    let tmp = c.genx(n.sons[0], newflags)
     if dest < 0: dest = c.getTemp(n.typ)
-    gABC(c, n, opc, dest, tmp)
+    if not isAddr:
+      gABC(c, n, opc, dest, tmp)
+      if gfAddrOf notin flags and fitsRegister(n.typ):
+        c.gABC(n, opcNodeToReg, dest, dest)
+    elif c.prc.slots[tmp].kind >= slotTempUnknown:
+      gABC(c, n, opcAddrNode, dest, tmp)
+    else:
+      gABC(c, n, opcAddrReg, dest, tmp)
     c.freeTemp(tmp)
 
 proc whichAsgnOpc(n: PNode): TOpcode =
@@ -940,8 +1022,7 @@ proc whichAsgnOpc(n: PNode): TOpcode =
 
 proc isRef(t: PType): bool = t.skipTypes(abstractRange-{tyTypeDesc}).kind == tyRef
 
-proc whichAsgnOpc(n: PNode; opc: TOpcode): TOpcode =
-  if isRef(n.typ): succ(opc) else: opc
+proc whichAsgnOpc(n: PNode; opc: TOpcode): TOpcode = opc
 
 proc genAsgn(c: PCtx; dest: TDest; ri: PNode; requiresCopy: bool) =
   let tmp = c.genx(ri)
@@ -949,8 +1030,6 @@ proc genAsgn(c: PCtx; dest: TDest; ri: PNode; requiresCopy: bool) =
   gABC(c, ri, whichAsgnOpc(ri), dest, tmp)
   c.freeTemp(tmp)
 
-template isGlobal(s: PSym): bool = sfGlobal in s.flags and s.kind != skForVar
-
 proc setSlot(c: PCtx; v: PSym) =
   # XXX generate type initialization here?
   if v.position == 0:
@@ -959,40 +1038,71 @@ proc setSlot(c: PCtx; v: PSym) =
         kind: if v.kind == skLet: slotFixedLet else: slotFixedVar)
     inc c.prc.maxSlots
 
+proc cannotEval(n: PNode) {.noinline.} =
+  globalError(n.info, errGenerated, "cannot evaluate at compile time: " &
+    n.renderTree)
+
+proc isOwnedBy(a, b: PSym): bool =
+  var a = a.owner
+  while a != nil and a.kind != skModule:
+    if a == b: return true
+    a = a.owner
+
+proc getOwner(c: PCtx): PSym =
+  result = c.prc.sym
+  if result.isNil: result = c.module
+
+proc checkCanEval(c: PCtx; n: PNode) =
+  # we need to ensure that we don't evaluate 'x' here:
+  # proc foo() = var x ...
+  let s = n.sym
+  if s.position == 0:
+    if s.kind in {skVar, skTemp, skLet, skParam, skResult} and 
+        not s.isOwnedBy(c.prc.sym) and s.owner != c.module:
+      cannotEval(n)
+
 proc genAsgn(c: PCtx; le, ri: PNode; requiresCopy: bool) =
   case le.kind
   of nkBracketExpr:
-    let dest = c.genx(le.sons[0])
+    let dest = c.genx(le.sons[0], {gfAddrOf})
     let idx = c.genx(le.sons[1])
     let tmp = c.genx(ri)
     if le.sons[0].typ.skipTypes(abstractVarRange-{tyTypeDesc}).kind in {
         tyString, tyCString}:
       c.gABC(le, opcWrStrIdx, dest, idx, tmp)
     else:
-      c.gABC(le, whichAsgnOpc(le, opcWrArr), dest, idx, tmp)
+      c.gABC(le, opcWrArr, dest, idx, tmp)
     c.freeTemp(tmp)
   of nkDotExpr, nkCheckedFieldExpr:
     # XXX field checks here
     let left = if le.kind == nkDotExpr: le else: le.sons[0]
-    let dest = c.genx(left.sons[0])
-    let idx = c.genx(left.sons[1])
+    let dest = c.genx(left.sons[0], {gfAddrOf})
+    let idx = genField(left.sons[1])
+    let tmp = c.genx(ri)
+    c.gABC(left, opcWrObj, dest, idx, tmp)
+    c.freeTemp(tmp)
+  of nkDerefExpr, nkHiddenDeref:
+    let dest = c.genx(le.sons[0], {gfAddrOf})
     let tmp = c.genx(ri)
-    c.gABC(left, whichAsgnOpc(left, opcWrObj), dest, idx, tmp)
+    c.gABC(le, opcWrDeref, dest, tmp)
     c.freeTemp(tmp)
   of nkSym:
     let s = le.sym
+    checkCanEval(c, le)
     if s.isGlobal:
       withTemp(tmp, le.typ):
-        gen(c, ri, tmp)
-        c.gABx(le, whichAsgnOpc(le, opcWrGlobal), tmp, s.position)
+        c.gen(le, tmp, {gfAddrOf})
+        let val = c.genx(ri)
+        c.gABC(le, opcWrDeref, tmp, val)
+        c.freeTemp(val)
     else:
-      if s.kind == skForVar and c.mode == emRepl: c.setSlot s
+      if s.kind == skForVar: c.setSlot s
       internalAssert s.position > 0 or (s.position == 0 and
                                         s.kind in {skParam,skResult})
       var dest: TRegister = s.position + ord(s.kind == skParam)
       gen(c, ri, dest)
   else:
-    let dest = c.genx(le)
+    let dest = c.genx(le, {gfAddrOf})
     genAsgn(c, dest, ri, requiresCopy)
 
 proc genLit(c: PCtx; n: PNode; dest: var TDest) =
@@ -1018,22 +1128,22 @@ proc importcSym(c: PCtx; info: TLineInfo; s: PSym) =
     localError(info, errGenerated,
                "cannot 'importc' variable at compile time")
 
-proc cannotEval(n: PNode) {.noinline.} =
-  globalError(n.info, errGenerated, "cannot evaluate at compile time: " &
-    n.renderTree)
+proc getNullValue*(typ: PType, info: TLineInfo): PNode
 
 proc genGlobalInit(c: PCtx; n: PNode; s: PSym) =
-  c.globals.add(emptyNode.copyNode)
+  c.globals.add(getNullValue(s.typ, n.info))
   s.position = c.globals.len
   # This is rather hard to support, due to the laziness of the VM code
   # generator. See tests/compile/tmacro2 for why this is necesary:
   #   var decls{.compileTime.}: seq[PNimrodNode] = @[]
-  c.gABx(n, opcGlobalOnce, 0, s.position)
+  let dest = c.getTemp(s.typ)
+  c.gABx(n, opcLdGlobal, dest, s.position)
   let tmp = c.genx(s.ast)
-  c.gABx(n, whichAsgnOpc(n, opcWrGlobal), tmp, s.position)
+  c.gABC(n, opcWrDeref, dest, tmp)
+  c.freeTemp(dest)
   c.freeTemp(tmp)
 
-proc genRdVar(c: PCtx; n: PNode; dest: var TDest) =
+proc genRdVar(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) =
   let s = n.sym
   if s.isGlobal:
     if sfCompileTime in s.flags or c.mode == emRepl:
@@ -1043,17 +1153,21 @@ proc genRdVar(c: PCtx; n: PNode; dest: var TDest) =
     if s.position == 0:
       if sfImportc in s.flags: c.importcSym(n.info, s)
       else: genGlobalInit(c, n, s)
-    if dest < 0:
-      dest = c.getGlobalSlot(n, s)
-      #c.gABx(n, opcAliasGlobal, dest, s.position)
+    if dest < 0: dest = c.getTemp(n.typ)
+    if gfAddrOf notin flags and fitsRegister(s.typ):
+      var cc = c.getTemp(n.typ)
+      c.gABx(n, opcLdGlobal, cc, s.position)
+      c.gABC(n, opcNodeToReg, dest, cc)
+      c.freeTemp(cc)
     else:
       c.gABx(n, opcLdGlobal, dest, s.position)
   else:
-    if s.kind == skForVar and c.mode == emRepl: c.setSlot s
+    if s.kind == skForVar and c.mode == emRepl: c.setSlot(s)
     if s.position > 0 or (s.position == 0 and
                           s.kind in {skParam,skResult}):
       if dest < 0:
         dest = s.position + ord(s.kind == skParam)
+        internalAssert(c.prc.slots[dest].kind < slotSomeTemp)
       else:
         # we need to generate an assignment:
         genAsgn(c, dest, n, c.prc.slots[dest].kind >= slotSomeTemp)
@@ -1061,30 +1175,45 @@ proc genRdVar(c: PCtx; n: PNode; dest: var TDest) =
       # see tests/t99bott for an example that triggers it:
       cannotEval(n)
 
-proc genAccess(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode;
-               flags: TGenFlags) =
+proc genArrAccess2(c: PCtx; n: PNode; dest: var TDest; opc: TOpcode;
+                   flags: TGenFlags) =
   let a = c.genx(n.sons[0], flags)
   let b = c.genx(n.sons[1], {})
   if dest < 0: dest = c.getTemp(n.typ)
-  c.gABC(n, (if gfAddrOf in flags: succ(opc) else: opc), dest, a, b)
+  if gfAddrOf notin flags and fitsRegister(n.typ):
+    var cc = c.getTemp(n.typ)
+    c.gABC(n, opc, cc, a, b)
+    c.gABC(n, opcNodeToReg, dest, cc)
+    c.freeTemp(cc)
+  else:
+    c.gABC(n, opc, dest, a, b)
   c.freeTemp(a)
   c.freeTemp(b)
 
 proc genObjAccess(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) =
-  genAccess(c, n, dest, opcLdObj, flags)
+  let a = c.genx(n.sons[0], flags)
+  let b = genField(n.sons[1])
+  if dest < 0: dest = c.getTemp(n.typ)
+  if gfAddrOf notin flags and fitsRegister(n.typ.skipTypes({tyVar})):
+    var cc = c.getTemp(n.typ)
+    c.gABC(n, opcLdObj, cc, a, b)
+    c.gABC(n, opcNodeToReg, dest, cc)
+    c.freeTemp(cc)
+  else:
+    c.gABC(n, opcLdObj, dest, a, b)
+  c.freeTemp(a)
 
 proc genCheckedObjAccess(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) =
   # XXX implement field checks!
-  genAccess(c, n.sons[0], dest, opcLdObj, flags)
+  genObjAccess(c, n.sons[0], dest, flags)
 
 proc genArrAccess(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags) =
   if n.sons[0].typ.skipTypes(abstractVarRange-{tyTypeDesc}).kind in {
       tyString, tyCString}:
-    genAccess(c, n, dest, opcLdStrIdx, {})
+    genArrAccess2(c, n, dest, opcLdStrIdx, {})
   else:
-    genAccess(c, n, dest, opcLdArr, flags)
+    genArrAccess2(c, n, dest, opcLdArr, flags)
 
-proc getNullValue*(typ: PType, info: TLineInfo): PNode
 proc getNullValueAux(obj: PNode, result: PNode) = 
   case obj.kind
   of nkRecList:
@@ -1137,50 +1266,51 @@ proc getNullValue(typ: PType, info: TLineInfo): PNode =
     result = newNodeIT(nkCurly, info, t)
   else: internalError("getNullValue: " & $t.kind)
 
+proc ldNullOpcode(t: PType): TOpcode =
+  if fitsRegister(t): opcLdNullReg else: opcLdNull
+
 proc genVarSection(c: PCtx; n: PNode) =
   for a in n:
     if a.kind == nkCommentStmt: continue
     #assert(a.sons[0].kind == nkSym) can happen for transformed vars
     if a.kind == nkVarTuple:
-      let tmp = c.genx(a.lastSon)
       for i in 0 .. a.len-3:
         setSlot(c, a[i].sym)
-        # v = t[i]
-        var v: TDest = -1
-        genRdVar(c, a[i], v)
-        c.gABC(n, opcLdObj, v, tmp, i)
-        # XXX globals?
-      c.freeTemp(tmp)
+        checkCanEval(c, a[i])
+      c.gen(lowerTupleUnpacking(a, c.getOwner))
     elif a.sons[0].kind == nkSym:
       let s = a.sons[0].sym
+      checkCanEval(c, a.sons[0])
       if s.isGlobal:
         if s.position == 0:
           if sfImportc in s.flags: c.importcSym(a.info, s)
           else:
-            let sa = if s.ast.isNil: getNullValue(s.typ, a.info) else: s.ast
+            let sa = if s.ast.isNil: getNullValue(s.typ, a.info) 
+                     else: canonValue(s.ast)
             c.globals.add(sa)
             s.position = c.globals.len
-            # "Once support" is unnecessary here
         if a.sons[2].kind == nkEmpty:
           when false:
             withTemp(tmp, s.typ):
               c.gABx(a, opcLdNull, tmp, c.genType(s.typ))
               c.gABx(a, whichAsgnOpc(a.sons[0], opcWrGlobal), tmp, s.position)
         else:
-          let tmp = genx(c, a.sons[2])
-          c.gABx(a, whichAsgnOpc(a.sons[0], opcWrGlobal), tmp, s.position)
+          let tmp = c.genx(a.sons[0], {gfAddrOf})
+          let val = c.genx(a.sons[2])
+          c.gABC(a, opcWrDeref, tmp, val)
+          c.freeTemp(val)
           c.freeTemp(tmp)
       else:
         setSlot(c, s)
         if a.sons[2].kind == nkEmpty:
-          c.gABx(a, opcLdNull, s.position, c.genType(s.typ))
+          c.gABx(a, ldNullOpcode(s.typ), s.position, c.genType(s.typ))
         else:
           gen(c, a.sons[2], s.position.TRegister)
     else:
       # assign to a.sons[0]; happens for closures
       if a.sons[2].kind == nkEmpty:
         let tmp = genx(c, a.sons[0])
-        c.gABx(a, opcLdNull, tmp, c.genType(a.sons[0].typ))
+        c.gABx(a, ldNullOpcode(a[0].typ), tmp, c.genType(a.sons[0].typ))
         c.freeTemp(tmp)
       else:
         genAsgn(c, a.sons[0], a.sons[2], true)
@@ -1188,10 +1318,19 @@ proc genVarSection(c: PCtx; n: PNode) =
 proc genArrayConstr(c: PCtx, n: PNode, dest: var TDest) =
   if dest < 0: dest = c.getTemp(n.typ)
   c.gABx(n, opcLdNull, dest, c.genType(n.typ))
+
+  let intType = getSysType(tyInt)
+  let seqType = n.typ.skipTypes(abstractVar-{tyTypeDesc})
+  if seqType.kind == tySequence:
+    var tmp = c.getTemp(intType)
+    c.gABx(n, opcLdImmInt, tmp, n.len)
+    c.gABx(n, opcNewSeq, dest, c.genType(seqType))
+    c.gABx(n, opcNewSeq, tmp, 0)
+    c.freeTemp(tmp)
+  
   if n.len > 0:
-    let intType = getSysType(tyInt)
     var tmp = getTemp(c, intType)
-    c.gABx(n, opcLdNull, tmp, c.genType(intType))
+    c.gABx(n, opcLdNullReg, tmp, c.genType(intType))
     for x in n:
       let a = c.genx(x)
       c.gABC(n, whichAsgnOpc(x, opcWrArr), dest, tmp, a)
@@ -1224,11 +1363,10 @@ proc genObjConstr(c: PCtx, n: PNode, dest: var TDest) =
   for i in 1.. <n.len:
     let it = n.sons[i]
     if it.kind == nkExprColonExpr and it.sons[0].kind == nkSym:
-      let idx = c.genx(it.sons[0])
+      let idx = genField(it.sons[0])
       let tmp = c.genx(it.sons[1])
       c.gABC(it, whichAsgnOpc(it.sons[1], opcWrObj), dest, idx, tmp)
       c.freeTemp(tmp)
-      c.freeTemp(idx)
     else:
       internalError(n.info, "invalid object constructor")
 
@@ -1239,11 +1377,10 @@ proc genTupleConstr(c: PCtx, n: PNode, dest: var TDest) =
   for i in 0.. <n.len:
     let it = n.sons[i]
     if it.kind == nkExprColonExpr:
-      let idx = c.genx(it.sons[0])
+      let idx = genField(it.sons[0])
       let tmp = c.genx(it.sons[1])
       c.gABC(it, whichAsgnOpc(it.sons[1], opcWrObj), dest, idx, tmp)
       c.freeTemp(tmp)
-      c.freeTemp(idx)
     else:
       let tmp = c.genx(it)
       c.gABC(it, whichAsgnOpc(it, opcWrObj), dest, i.TRegister, tmp)
@@ -1255,10 +1392,11 @@ proc gen(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}) =
   case n.kind
   of nkSym:
     let s = n.sym
+    checkCanEval(c, n)
     case s.kind
     of skVar, skForVar, skTemp, skLet, skParam, skResult:
-      genRdVar(c, n, dest)
-    of skProc, skConverter, skMacro, skTemplate, skMethod, skIterator:
+      genRdVar(c, n, dest, flags)
+    of skProc, skConverter, skMacro, skTemplate, skMethod, skIterators:
       # 'skTemplate' is only allowed for 'getAst' support:
       if sfImportc in s.flags: c.importcSym(n.info, s)
       genLit(c, n, dest)
@@ -1271,12 +1409,6 @@ proc gen(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}) =
       else:
         var lit = genLiteral(c, newIntNode(nkIntLit, s.position))
         c.gABx(n, opcLdConst, dest, lit)
-    of skField:
-      internalAssert dest < 0
-      if s.position > high(dest):
-        internalError(n.info, 
-          "too large offset! cannot generate code for: " & s.name.s)
-      dest = s.position
     of skType:
       genTypeLit(c, s.typ, dest)
     else:
@@ -1303,8 +1435,8 @@ proc gen(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}) =
   of nkDotExpr: genObjAccess(c, n, dest, flags)
   of nkCheckedFieldExpr: genCheckedObjAccess(c, n, dest, flags)
   of nkBracketExpr: genArrAccess(c, n, dest, flags)
-  of nkDerefExpr, nkHiddenDeref: genAddrDeref(c, n, dest, opcDeref, flags)
-  of nkAddr, nkHiddenAddr: genAddrDeref(c, n, dest, opcAddr, flags)
+  of nkDerefExpr, nkHiddenDeref: genAddrDeref(c, n, dest, opcLdDeref, flags)
+  of nkAddr, nkHiddenAddr: genAddrDeref(c, n, dest, opcAddrNode, flags)
   of nkWhenStmt, nkIfStmt, nkIfExpr: genIf(c, n, dest)
   of nkCaseStmt: genCase(c, n, dest)
   of nkWhileStmt:
@@ -1423,7 +1555,7 @@ proc optimizeJumps(c: PCtx; start: int) =
       var d = i + c.code[i].jmpDiff
       for iters in countdown(maxIterations, 0):
         case c.code[d].opcode
-        of opcJmp:
+        of opcJmp, opcJmpBack:
           d = d + c.code[d].jmpDiff
         of opcTJmp, opcFJmp:
           if c.code[d].regA != reg: break
@@ -1441,7 +1573,7 @@ proc optimizeJumps(c: PCtx; start: int) =
         else: break
       if d != i + c.code[i].jmpDiff:
         c.finalJumpTarget(i, d - i)
-    of opcJmp:
+    of opcJmp, opcJmpBack:
       var d = i + c.code[i].jmpDiff
       var iters = maxIterations
       while c.code[d].opcode == opcJmp and iters > 0:
@@ -1472,7 +1604,7 @@ proc genProc(c: PCtx; s: PSym): int =
     # procs easily:
     let body = s.getBody
     let procStart = c.xjmp(body, opcJmp, 0)
-    var p = PProc(blocks: @[])
+    var p = PProc(blocks: @[], sym: s)
     let oldPrc = c.prc
     c.prc = p
     # iterate over the parameters and allocate space for them:
@@ -1489,9 +1621,9 @@ proc genProc(c: PCtx; s: PSym): int =
     c.gABC(body, opcEof, eofInstr.regA)
     c.optimizeJumps(result)
     s.offset = c.prc.maxSlots
-    #if s.name.s == "concatStyleInterpolation":
+    #if s.name.s == "addStuff":
+    #  echo renderTree(body)
     #  c.echoCode(result)
-    # echo renderTree(body)
     c.prc = oldPrc
   else:
     c.prc.maxSlots = s.offset
diff --git a/compiler/wordrecg.nim b/compiler/wordrecg.nim
index 837bb4f50..9fdb3bac6 100644
--- a/compiler/wordrecg.nim
+++ b/compiler/wordrecg.nim
@@ -62,8 +62,8 @@ type
     wWatchPoint, wSubsChar, 
     wAcyclic, wShallow, wUnroll, wLinearScanEnd, wComputedGoto, wInjectStmt,
     wWrite, wGensym, wInject, wDirty, wInheritable, wThreadVar, wEmit, 
-    wNoStackFrame,
-    wImplicitStatic, wGlobal, wCodegenDecl,
+    wAsmNoStackFrame,
+    wImplicitStatic, wGlobal, wCodegenDecl, wUnchecked,
 
     wAuto, wBool, wCatch, wChar, wClass,
     wConst_cast, wDefault, wDelete, wDouble, wDynamic_cast,
@@ -72,7 +72,7 @@ type
     wPrivate, wProtected, wPublic, wRegister, wReinterpret_cast,
     wShort, wSigned, wSizeof, wStatic_cast, wStruct, wSwitch,
     wThis, wThrow, wTrue, wTypedef, wTypeid, wTypename,
-    wUnion, wUnsigned, wVirtual, wVoid, wVolatile, wWchar_t,
+    wUnion, wPacked, wUnsigned, wVirtual, wVoid, wVolatile, wWchar_t,
 
     wAlignas, wAlignof, wConstexpr, wDecltype, wNullptr, wNoexcept,
     wThread_local, wStatic_assert, wChar16_t, wChar32_t,
@@ -145,7 +145,7 @@ const
     "subschar", "acyclic", "shallow", "unroll", "linearscanend",
     "computedgoto", "injectstmt",
     "write", "gensym", "inject", "dirty", "inheritable", "threadvar", "emit",
-    "nostackframe", "implicitstatic", "global", "codegendecl",
+    "asmnostackframe", "implicitstatic", "global", "codegendecl", "unchecked",
     
     "auto", "bool", "catch", "char", "class",
     "const_cast", "default", "delete", "double",
@@ -155,7 +155,7 @@ const
     "private", "protected", "public", "register", "reinterpret_cast",
     "short", "signed", "sizeof", "static_cast", "struct", "switch",
     "this", "throw", "true", "typedef", "typeid",
-    "typename", "union", "unsigned", "virtual", "void", "volatile",
+    "typename", "union", "packed", "unsigned", "virtual", "void", "volatile",
     "wchar_t",
 
     "alignas", "alignof", "constexpr", "decltype", "nullptr", "noexcept",