'bind' as a declarative statement

10 files changed, 102 insertions, 60 deletions

diff --git a/compiler/ast.nim b/compiler/ast.nim
index 89aba40c6..fd79c90e0 100755
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -162,6 +162,7 @@ type
     nkImportStmt,         # an import statement
     nkFromStmt,           # a from * import statement
     nkIncludeStmt,        # an include statement
+    nkBindStmt,           # a bind statement
     nkCommentStmt,        # a comment statement
     nkStmtListExpr,       # a statement list followed by an expr; this is used
                           # to allow powerful multi-line templates
diff --git a/compiler/astalgo.nim b/compiler/astalgo.nim
index 17875d524..b06194daf 100755
--- a/compiler/astalgo.nim
+++ b/compiler/astalgo.nim
@@ -100,10 +100,12 @@ proc OpenScope*(tab: var TSymTab)
 proc RawCloseScope*(tab: var TSymTab)
   # the real "closeScope" adds some
   # checks in parsobj
-  # these are for debugging only:
-proc debug*(n: PSym)
-proc debug*(n: PType)
-proc debug*(n: PNode)
+
+# these are for debugging only: They are not really deprecated, but I want
+# the warning so that release versions do not contain debugging statements:
+proc debug*(n: PSym) {.deprecated.}
+proc debug*(n: PType) {.deprecated.}
+proc debug*(n: PNode) {.deprecated.}
 
 # --------------------------- ident tables ----------------------------------
 proc IdTableGet*(t: TIdTable, key: PIdObj): PObject
diff --git a/compiler/evals.nim b/compiler/evals.nim
index b1d3688c3..876f800d9 100755
--- a/compiler/evals.nim
+++ b/compiler/evals.nim
@@ -822,7 +822,7 @@ proc evalTemplateArgs(n: PNode, s: PSym): PNode =
     addSon(result, arg)
 
 var evalTemplateCounter = 0
-  # to prevend endless recursion in templates instantation
+  # to prevent endless recursion in templates instantation
 
 proc evalTemplate(n: PNode, sym: PSym): PNode = 
   inc(evalTemplateCounter)
diff --git a/compiler/extccomp.nim b/compiler/extccomp.nim
index 8fa52b5d2..cf4d85dc8 100755
--- a/compiler/extccomp.nim
+++ b/compiler/extccomp.nim
@@ -239,9 +239,9 @@ const
      asmStmtFrmt: "asm($1);$n", 
      props: {hasSwitchRange, hasComputedGoto, hasCpp})]
 
-var ccompiler*: TSystemCC = ccGcc
+var ccompiler*: TSystemCC = ccGcc # the used compiler
 
-const                   # the used compiler
+const               
   hExt* = "h"
 
 var cExt*: string = "c" # extension of generated C/C++ files
diff --git a/compiler/parser.nim b/compiler/parser.nim
index 544cbae87..d1798efa4 100755
--- a/compiler/parser.nim
+++ b/compiler/parser.nim
@@ -212,20 +212,20 @@ proc parseSymbol(p: var TParser): PNode =
 proc indexExpr(p: var TParser): PNode = 
   result = parseExpr(p)
 
-proc indexExprList(p: var TParser, first: PNode): PNode = 
-  result = newNodeP(nkBracketExpr, p)
+proc indexExprList(p: var TParser, first: PNode, k: TNodeKind, 
+                   endToken: TTokType): PNode = 
+  result = newNodeP(k, p)
   addSon(result, first)
   getTok(p)
   optInd(p, result)
-  while (p.tok.tokType != tkBracketRi) and (p.tok.tokType != tkEof) and
-      (p.tok.tokType != tkSad): 
+  while p.tok.tokType notin {endToken, tkEof, tkSad}:
     var a = indexExpr(p)
     addSon(result, a)
     if p.tok.tokType != tkComma: break 
     getTok(p)
     optInd(p, a)
   optPar(p)
-  eat(p, tkBracketRi)
+  eat(p, endToken)
 
 proc exprColonEqExpr(p: var TParser, kind: TNodeKind, tok: TTokType): PNode = 
   var a = parseExpr(p)
@@ -460,13 +460,9 @@ proc primary(p: var TParser): PNode =
       addSon(result, parseSymbol(p))
       result = parseGStrLit(p, result)
     of tkBracketLe: 
-      result = indexExprList(p, result)
+      result = indexExprList(p, result, nkBracketExpr, tkBracketRi)
     of tkCurlyLe:
-      var a = result
-      result = newNodeP(nkCurlyExpr, p)
-      var b = setOrTableConstr(p)
-      result.add(a)
-      for i in 0 .. <b.len: result.add(b.sons[i])
+      result = indexExprList(p, result, nkCurlyExpr, tkCurlyRi)
     else: break
   
 proc lowestExprAux(p: var TParser, limit: int): PNode = 
@@ -1291,6 +1287,18 @@ proc parseVariable(p: var TParser): PNode =
   else: result = parseIdentColonEquals(p, {withPragma})
   indAndComment(p, result)    # special extension!
   
+proc parseBind(p: var TParser): PNode =
+  result = newNodeP(nkBindStmt, p)
+  getTok(p)
+  optInd(p, result)
+  while p.tok.tokType == tkSymbol: 
+    var a = newIdentNodeP(p.tok.ident, p)
+    getTok(p)
+    addSon(result, a)
+    if p.tok.tokType != tkComma: break 
+    getTok(p)
+    optInd(p, a)
+  
 proc simpleStmt(p: var TParser): PNode = 
   case p.tok.tokType
   of tkReturn: result = parseReturnOrRaise(p, nkReturnStmt)
@@ -1329,6 +1337,7 @@ proc complexOrSimpleStmt(p: var TParser): PNode =
   of tkLet: result = parseSection(p, nkLetSection, parseConstant)
   of tkWhen: result = parseIfOrWhen(p, nkWhenStmt)
   of tkVar: result = parseSection(p, nkVarSection, parseVariable)
+  of tkBind: result = parseBind(p)
   else: result = simpleStmt(p)
   
 proc parseStmt(p: var TParser): PNode = 
diff --git a/compiler/renderer.nim b/compiler/renderer.nim
index 783f0bd40..316e1f42f 100755
--- a/compiler/renderer.nim
+++ b/compiler/renderer.nim
@@ -345,6 +345,7 @@ proc lsub(n: PNode): int =
   of nkTupleTy: result = lcomma(n) + len("tuple[]")
   of nkDotExpr: result = lsons(n) + 1
   of nkBind: result = lsons(n) + len("bind_")
+  of nkBindStmt: result = lcomma(n) + len("bind_")
   of nkCheckedFieldExpr: result = lsub(n.sons[0])
   of nkLambda: result = lsons(n) + len("lambda__=_")
   of nkConstDef, nkIdentDefs: 
@@ -1027,6 +1028,9 @@ proc gsub(g: var TSrcGen, n: PNode, c: TContext) =
     putWithSpace(g, tkColon, ":")
     gcoms(g)
     gstmts(g, lastSon(n), c)
+  of nkBindStmt: 
+    putWithSpace(g, tkBind, "bind")
+    gcomma(g, n, c)
   of nkElifBranch: 
     optNL(g)
     putWithSpace(g, tkElif, "elif")
diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim
index 9eed486e9..708e3055d 100755
--- a/compiler/semexprs.nim
+++ b/compiler/semexprs.nim
@@ -1207,7 +1207,8 @@ proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode =
     if result.kind == nkDotCall: 
       result.kind = nkCall
       result = semExpr(c, result, flags)
-  of nkBind: 
+  of nkBind:
+    Message(n.info, warnDeprecated, "bind")
     result = semExpr(c, n.sons[0], flags)
   of nkCall, nkInfix, nkPrefix, nkPostfix, nkCommand, nkCallStrLit: 
     # check if it is an expression macro:
diff --git a/compiler/semgnrc.nim b/compiler/semgnrc.nim
index 3530ff2af..d8f16e559 100755
--- a/compiler/semgnrc.nim
+++ b/compiler/semgnrc.nim
@@ -20,11 +20,13 @@ type
     withinBind, withinTypeDesc
   TSemGenericFlags = set[TSemGenericFlag]
 
-proc semGenericStmt(c: PContext, n: PNode, flags: TSemGenericFlags): PNode
+proc semGenericStmt(c: PContext, n: PNode, flags: TSemGenericFlags,
+                    toBind: var TIntSet): PNode
 proc semGenericStmtScope(c: PContext, n: PNode, 
-                         flags: TSemGenericFlags): PNode = 
+                         flags: TSemGenericFlags,
+                         toBind: var TIntSet): PNode = 
   openScope(c.tab)
-  result = semGenericStmt(c, n, flags)
+  result = semGenericStmt(c, n, flags, toBind)
   closeScope(c.tab)
 
 proc semGenericStmtSymbol(c: PContext, n: PNode, s: PSym): PNode = 
@@ -60,7 +62,7 @@ proc getIdentNode(n: PNode): PNode =
     result = n
 
 proc semGenericStmt(c: PContext, n: PNode, 
-                    flags: TSemGenericFlags): PNode = 
+                    flags: TSemGenericFlags, toBind: var TIntSet): PNode = 
   result = n
   if gCmd == cmdIdeTools: suggestStmt(c, n)
   case n.kind
@@ -68,10 +70,10 @@ proc semGenericStmt(c: PContext, n: PNode,
     var s = SymtabGet(c.Tab, n.ident)
     if s == nil:
       # no error if symbol cannot be bound, unless in ``bind`` context:
-      if withinBind in flags: 
+      if withinBind in flags:
         localError(n.info, errUndeclaredIdentifier, n.ident.s)
     else:
-      if withinBind in flags: result = symChoice(c, n, s)
+      if withinBind in flags or s.name.id in toBind: result = symChoice(c, n, s)
       else: result = semGenericStmtSymbol(c, n, s)
   of nkDotExpr: 
     var s = QualifiedLookUp(c, n, {})
@@ -80,7 +82,9 @@ proc semGenericStmt(c: PContext, n: PNode,
   of nkEmpty, nkSym..nkNilLit: 
     nil
   of nkBind: 
-    result = semGenericStmt(c, n.sons[0], flags+{withinBind})
+    result = semGenericStmt(c, n.sons[0], flags+{withinBind}, toBind)
+  of nkBindStmt:
+    result = semBindStmt(c, n, toBind)
   of nkCall, nkHiddenCallConv, nkInfix, nkPrefix, nkCommand, nkCallStrLit: 
     # check if it is an expression macro:
     checkMinSonsLen(n, 1)
@@ -112,52 +116,53 @@ proc semGenericStmt(c: PContext, n: PNode,
         result.sons[0] = newSymNode(s, n.sons[0].info)
         first = 1
     for i in countup(first, sonsLen(result) - 1): 
-      result.sons[i] = semGenericStmt(c, result.sons[i], flags)
+      result.sons[i] = semGenericStmt(c, result.sons[i], flags, toBind)
   of nkMacroStmt: 
     result = semMacroStmt(c, n, false)
     for i in countup(0, sonsLen(result)-1): 
-      result.sons[i] = semGenericStmt(c, result.sons[i], flags)
+      result.sons[i] = semGenericStmt(c, result.sons[i], flags, toBind)
   of nkIfStmt: 
     for i in countup(0, sonsLen(n)-1): 
-      n.sons[i] = semGenericStmtScope(c, n.sons[i], flags)
+      n.sons[i] = semGenericStmtScope(c, n.sons[i], flags, toBind)
   of nkWhileStmt: 
     openScope(c.tab)
     for i in countup(0, sonsLen(n)-1): 
-      n.sons[i] = semGenericStmt(c, n.sons[i], flags)
+      n.sons[i] = semGenericStmt(c, n.sons[i], flags, toBind)
     closeScope(c.tab)
   of nkCaseStmt: 
     openScope(c.tab)
-    n.sons[0] = semGenericStmt(c, n.sons[0], flags)
+    n.sons[0] = semGenericStmt(c, n.sons[0], flags, toBind)
     for i in countup(1, sonsLen(n)-1): 
       var a = n.sons[i]
       checkMinSonsLen(a, 1)
       var L = sonsLen(a)
-      for j in countup(0, L-2): a.sons[j] = semGenericStmt(c, a.sons[j], flags)
-      a.sons[L - 1] = semGenericStmtScope(c, a.sons[L-1], flags)
+      for j in countup(0, L-2): 
+        a.sons[j] = semGenericStmt(c, a.sons[j], flags, toBind)
+      a.sons[L - 1] = semGenericStmtScope(c, a.sons[L-1], flags, toBind)
     closeScope(c.tab)
   of nkForStmt: 
     var L = sonsLen(n)
     openScope(c.tab)
-    n.sons[L - 2] = semGenericStmt(c, n.sons[L-2], flags)
+    n.sons[L - 2] = semGenericStmt(c, n.sons[L-2], flags, toBind)
     for i in countup(0, L - 3): addDecl(c, newSymS(skUnknown, n.sons[i], c))
-    n.sons[L - 1] = semGenericStmt(c, n.sons[L-1], flags)
+    n.sons[L - 1] = semGenericStmt(c, n.sons[L-1], flags, toBind)
     closeScope(c.tab)
   of nkBlockStmt, nkBlockExpr, nkBlockType: 
     checkSonsLen(n, 2)
     openScope(c.tab)
     if n.sons[0].kind != nkEmpty: addDecl(c, newSymS(skUnknown, n.sons[0], c))
-    n.sons[1] = semGenericStmt(c, n.sons[1], flags)
+    n.sons[1] = semGenericStmt(c, n.sons[1], flags, toBind)
     closeScope(c.tab)
   of nkTryStmt: 
     checkMinSonsLen(n, 2)
-    n.sons[0] = semGenericStmtScope(c, n.sons[0], flags)
+    n.sons[0] = semGenericStmtScope(c, n.sons[0], flags, toBind)
     for i in countup(1, sonsLen(n)-1): 
       var a = n.sons[i]
       checkMinSonsLen(a, 1)
       var L = sonsLen(a)
       for j in countup(0, L-2): 
-        a.sons[j] = semGenericStmt(c, a.sons[j], flags+{withinTypeDesc})
-      a.sons[L-1] = semGenericStmtScope(c, a.sons[L-1], flags)
+        a.sons[j] = semGenericStmt(c, a.sons[j], flags+{withinTypeDesc}, toBind)
+      a.sons[L-1] = semGenericStmtScope(c, a.sons[L-1], flags, toBind)
   of nkVarSection: 
     for i in countup(0, sonsLen(n) - 1): 
       var a = n.sons[i]
@@ -165,8 +170,9 @@ proc semGenericStmt(c: PContext, n: PNode,
       if (a.kind != nkIdentDefs) and (a.kind != nkVarTuple): IllFormedAst(a)
       checkMinSonsLen(a, 3)
       var L = sonsLen(a)
-      a.sons[L-2] = semGenericStmt(c, a.sons[L-2], flags+{withinTypeDesc})
-      a.sons[L-1] = semGenericStmt(c, a.sons[L-1], flags)
+      a.sons[L-2] = semGenericStmt(c, a.sons[L-2], flags+{withinTypeDesc}, 
+                                   toBind)
+      a.sons[L-1] = semGenericStmt(c, a.sons[L-1], flags, toBind)
       for j in countup(0, L-3):
         addDecl(c, newSymS(skUnknown, getIdentNode(a.sons[j]), c))
   of nkGenericParams: 
@@ -175,7 +181,8 @@ proc semGenericStmt(c: PContext, n: PNode,
       if (a.kind != nkIdentDefs): IllFormedAst(a)
       checkMinSonsLen(a, 3)
       var L = sonsLen(a)
-      a.sons[L-2] = semGenericStmt(c, a.sons[L-2], flags+{withinTypeDesc}) 
+      a.sons[L-2] = semGenericStmt(c, a.sons[L-2], flags+{withinTypeDesc}, 
+                                   toBind) 
       # do not perform symbol lookup for default expressions 
       for j in countup(0, L-3): 
         addDecl(c, newSymS(skUnknown, getIdentNode(a.sons[j]), c))
@@ -186,8 +193,8 @@ proc semGenericStmt(c: PContext, n: PNode,
       if (a.kind != nkConstDef): IllFormedAst(a)
       checkSonsLen(a, 3)
       addDecl(c, newSymS(skUnknown, getIdentNode(a.sons[0]), c))
-      a.sons[1] = semGenericStmt(c, a.sons[1], flags+{withinTypeDesc})
-      a.sons[2] = semGenericStmt(c, a.sons[2], flags)
+      a.sons[1] = semGenericStmt(c, a.sons[1], flags+{withinTypeDesc}, toBind)
+      a.sons[2] = semGenericStmt(c, a.sons[2], flags, toBind)
   of nkTypeSection: 
     for i in countup(0, sonsLen(n) - 1): 
       var a = n.sons[i]
@@ -202,15 +209,15 @@ proc semGenericStmt(c: PContext, n: PNode,
       checkSonsLen(a, 3)
       if a.sons[1].kind != nkEmpty: 
         openScope(c.tab)
-        a.sons[1] = semGenericStmt(c, a.sons[1], flags)
-        a.sons[2] = semGenericStmt(c, a.sons[2], flags+{withinTypeDesc})
+        a.sons[1] = semGenericStmt(c, a.sons[1], flags, toBind)
+        a.sons[2] = semGenericStmt(c, a.sons[2], flags+{withinTypeDesc}, toBind)
         closeScope(c.tab)
       else: 
-        a.sons[2] = semGenericStmt(c, a.sons[2], flags+{withinTypeDesc})
+        a.sons[2] = semGenericStmt(c, a.sons[2], flags+{withinTypeDesc}, toBind)
   of nkEnumTy: 
     checkMinSonsLen(n, 1)
     if n.sons[0].kind != nkEmpty: 
-      n.sons[0] = semGenericStmt(c, n.sons[0], flags+{withinTypeDesc})
+      n.sons[0] = semGenericStmt(c, n.sons[0], flags+{withinTypeDesc}, toBind)
     for i in countup(1, sonsLen(n) - 1): 
       var a: PNode
       case n.sons[i].kind
@@ -223,14 +230,15 @@ proc semGenericStmt(c: PContext, n: PNode,
   of nkFormalParams: 
     checkMinSonsLen(n, 1)
     if n.sons[0].kind != nkEmpty: 
-      n.sons[0] = semGenericStmt(c, n.sons[0], flags+{withinTypeDesc})
+      n.sons[0] = semGenericStmt(c, n.sons[0], flags+{withinTypeDesc}, toBind)
     for i in countup(1, sonsLen(n) - 1): 
       var a = n.sons[i]
       if (a.kind != nkIdentDefs): IllFormedAst(a)
       checkMinSonsLen(a, 3)
       var L = sonsLen(a)
-      a.sons[L-2] = semGenericStmt(c, a.sons[L-2], flags+{withinTypeDesc})
-      a.sons[L-1] = semGenericStmt(c, a.sons[L-1], flags)
+      a.sons[L-2] = semGenericStmt(c, a.sons[L-2], flags+{withinTypeDesc}, 
+                                   toBind)
+      a.sons[L-1] = semGenericStmt(c, a.sons[L-1], flags, toBind)
       for j in countup(0, L-3): 
         addDecl(c, newSymS(skUnknown, getIdentNode(a.sons[j]), c))
   of nkProcDef, nkMethodDef, nkConverterDef, nkMacroDef, nkTemplateDef, 
@@ -238,15 +246,16 @@ proc semGenericStmt(c: PContext, n: PNode,
     checkSonsLen(n, codePos + 1)
     addDecl(c, newSymS(skUnknown, getIdentNode(n.sons[0]), c))
     openScope(c.tab)
-    n.sons[genericParamsPos] = semGenericStmt(c, n.sons[genericParamsPos], flags)
+    n.sons[genericParamsPos] = semGenericStmt(c, n.sons[genericParamsPos], 
+                                              flags, toBind)
     if n.sons[paramsPos].kind != nkEmpty: 
       if n.sons[paramsPos].sons[0].kind != nkEmpty: 
         addDecl(c, newSym(skUnknown, getIdent("result"), nil))
-      n.sons[paramsPos] = semGenericStmt(c, n.sons[paramsPos], flags)
-    n.sons[pragmasPos] = semGenericStmt(c, n.sons[pragmasPos], flags)
-    n.sons[codePos] = semGenericStmtScope(c, n.sons[codePos], flags)
+      n.sons[paramsPos] = semGenericStmt(c, n.sons[paramsPos], flags, toBind)
+    n.sons[pragmasPos] = semGenericStmt(c, n.sons[pragmasPos], flags, toBind)
+    n.sons[codePos] = semGenericStmtScope(c, n.sons[codePos], flags, toBind)
     closeScope(c.tab)
   else: 
     for i in countup(0, sonsLen(n) - 1): 
-      result.sons[i] = semGenericStmt(c, n.sons[i], flags)
+      result.sons[i] = semGenericStmt(c, n.sons[i], flags, toBind)
   
diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim
index 243c2ce00..1a8182437 100755
--- a/compiler/semstmts.nim
+++ b/compiler/semstmts.nim
@@ -700,9 +700,10 @@ proc semProcAux(c: PContext, n: PNode, kind: TSymKind,
       if s.typ.sons[0] != nil and kind != skIterator: addResultNode(c, n)
       popProcCon(c)
     else: 
-      if s.typ.sons[0] != nil and kind != skIterator: 
-        addDecl(c, newSym(skUnknown, getIdent("result"), nil))
-      n.sons[codePos] = semGenericStmtScope(c, n.sons[codePos], {})
+      if s.typ.sons[0] != nil and kind != skIterator:
+        addDecl(c, newSym(skUnknown, getIdent"result", nil))
+      var toBind = initIntSet()
+      n.sons[codePos] = semGenericStmtScope(c, n.sons[codePos], {}, toBind)
       fixupInstantiatedSymbols(c, s)
     if sfImportc in s.flags: 
       # so we just ignore the body after semantic checking for importc:
diff --git a/compiler/semtempl.nim b/compiler/semtempl.nim
index ff2dd3bb1..24395073d 100755
--- a/compiler/semtempl.nim
+++ b/compiler/semtempl.nim
@@ -96,6 +96,19 @@ proc symChoice(c: PContext, n: PNode, s: PSym): PNode =
       addSon(result, newSymNode(a))
       a = nextOverloadIter(o, c, n)
 
+proc semBindStmt(c: PContext, n: PNode, toBind: var TIntSet): PNode =
+  for i in 0 .. < n.len:
+    var a = n.sons[i]
+    if a.kind == nkIdent:
+      var s = SymtabGet(c.Tab, a.ident)
+      if s != nil:
+        toBind.incl(s.name.id)
+      else:
+        localError(a.info, errUndeclaredIdentifier, a.ident.s)
+    else: 
+      illFormedAst(a)
+  result = newNodeI(nkEmpty, n.info)
+
 proc resolveTemplateParams(c: PContext, n: PNode, withinBind: bool, 
                            toBind: var TIntSet): PNode = 
   var s: PSym
@@ -103,7 +116,7 @@ proc resolveTemplateParams(c: PContext, n: PNode, withinBind: bool,
   of nkIdent: 
     if not withinBind and not Contains(toBind, n.ident.id): 
       s = SymTabLocalGet(c.Tab, n.ident)
-      if (s != nil): 
+      if s != nil: 
         result = newSymNode(s)
         result.info = n.info
       else: 
@@ -115,6 +128,8 @@ proc resolveTemplateParams(c: PContext, n: PNode, withinBind: bool,
     result = n
   of nkBind: 
     result = resolveTemplateParams(c, n.sons[0], true, toBind)
+  of nkBindStmt:
+    result = semBindStmt(c, n, toBind)
   else: 
     result = n
     for i in countup(0, sonsLen(n) - 1):