added missing type flags

3 files changed, 21 insertions, 11 deletions

diff --git a/compiler/ast.nim b/compiler/ast.nim
index 39228da40..edf93f4c9 100755
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -347,7 +347,7 @@ type
     nfSem       # node has been checked for semantics
 
   TNodeFlags* = set[TNodeFlag]
-  TTypeFlag* = enum   # keep below 17 for efficiency reasons (now: 16)
+  TTypeFlag* = enum   # keep below 32 for efficiency reasons (now: 19)
     tfVarargs,        # procedure has C styled varargs
     tfNoSideEffect,   # procedure type does not allow side effects
     tfFinal,          # is the object final?
@@ -359,19 +359,22 @@ type
     tfFromGeneric,    # type is an instantiation of a generic; this is needed
                       # because for instantiations of objects, structural
                       # type equality has to be used
-    tfInstantiated    # XXX: used to mark generic params after instantiation.
+    tfInstantiated,   # XXX: used to mark generic params after instantiation.
                       # if the concrete type happens to be an implicit generic
                       # this can lead to invalid proc signatures in the second
                       # pass of semProcTypeNode performed after instantiation.
                       # this won't be needed if we don't perform this redundant
                       # second pass (stay tuned).
-    tfRetType         # marks return types in proc (used to detect type classes 
+    tfRetType,        # marks return types in proc (used to detect type classes 
                       # used as return types for return type inference)
     tfAll,            # type class requires all constraints to be met (default)
     tfAny,            # type class requires any constraint to be met
     tfCapturesEnv,    # whether proc really captures some environment
     tfByCopy,         # pass object/tuple by copy (C backend)
-    tfByRef           # pass object/tuple by reference (C backend)
+    tfByRef,          # pass object/tuple by reference (C backend)
+    tfIterator,       # type is really an iterator, not a tyProc
+    tfShared,         # type is 'shared'
+    tfNotNil          # type cannot be 'nil'
 
   TTypeFlags* = set[TTypeFlag]
 
@@ -412,6 +415,9 @@ const
     skMacro, skTemplate}
   tfIncompleteStruct* = tfVarargs
   skError* = skUnknown
+  
+  # type flags that are essential for type equality:
+  eqTypeFlags* = {tfIterator, tfShared, tfNotNil}
 
 type
   TMagic* = enum # symbols that require compiler magic:
diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index 6716693ca..ab80298de 100755
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -882,7 +882,7 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
   of nkPtrTy: result = semAnyRef(c, n, tyPtr, prev)
   of nkVarTy: result = semVarType(c, n, prev)
   of nkDistinctTy: result = semDistinct(c, n, prev)
-  of nkProcTy:
+  of nkProcTy, nkIteratorTy:
     if n.sonsLen == 0: return newConstraint(c, tyProc)
     checkSonsLen(n, 2)
     openScope(c.tab)
diff --git a/compiler/types.nim b/compiler/types.nim
index afc05d773..dbd03620c 100755
--- a/compiler/types.nim
+++ b/compiler/types.nim
@@ -339,9 +339,11 @@ proc canFormAcycleAux(marker: var TIntSet, typ: PType, startId: int): bool =
       if t.n != nil: result = canFormAcycleNode(marker, t.n, startId)
     else: 
       result = t.id == startId
-    if t.kind == tyObject and tfFinal notin t.flags:
-      # damn inheritance may introduce cycles:
-      result = true
+    # Inheritance can introduce cyclic types, however this is not relevant
+    # as the type that is passed to 'new' is statically known!
+    #if t.kind == tyObject and tfFinal notin t.flags:
+    #  # damn inheritance may introduce cycles:
+    #  result = true
   else: nil
 
 proc canFormAcycle(typ: PType): bool = 
@@ -410,7 +412,7 @@ proc TypeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
       "float", "float32", "float64", "float128",
       "uint", "uint8", "uint16", "uint32", "uint64",
       "bignum", "const ",
-      "!", "varargs[$1]", "iter[$1]", "Error Type", "TypeClass" ]
+      "!", "varargs[$1]", "iter[$1]", "Error Type", "TypeClass"]
   var t = typ
   result = ""
   if t == nil: return 
@@ -476,8 +478,8 @@ proc TypeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
     result = typeToStr[t.kind] & typeToString(t.sons[0])
   of tyRange: 
     result = "range " & rangeToStr(t.n)
-  of tyProc: 
-    result = "proc ("
+  of tyProc:
+    result = if tfIterator in t.flags: "iterator (" else: "proc ("
     for i in countup(1, sonsLen(t) - 1): 
       add(result, typeToString(t.sons[i]))
       if i < sonsLen(t) - 1: add(result, ", ")
@@ -497,6 +499,8 @@ proc TypeToString(typ: PType, prefer: TPreferedDesc = preferName): string =
     result = typeToStr[t.kind] % typeToString(t.sons[0])
   else: 
     result = typeToStr[t.kind]
+  if tfShared in t.flags: result = "shared " & result
+  if tfNotNil in t.flags: result.add(" not nil")
 
 proc resultType(t: PType): PType = 
   assert(t.kind == tyProc)