bugfix: overloading resolution for typeof

compiler/sem.nim

@@ -35,7 +35,7 @@ proc semStmtScope(c: PContext, n: PNode): PNode
 
 type 
   TExprFlag = enum 
-    efAllowType, efLValue, efWantIterator
+    efAllowType, efLValue, efWantIterator, efInTypeof
   TExprFlags = set[TExprFlag]
 
 proc semExpr(c: PContext, n: PNode, flags: TExprFlags = {}): PNode

compiler/semcall.nim

@@ -35,6 +35,8 @@ proc semDirectCallWithBinding(c: PContext, n, f: PNode, filter: TSymKinds,
       z.calleeSym = sym
       matches(c, n, z)
       if z.state == csMatch: 
+        # little hack so that iterators are preferred over everything else:
+        if sym.kind == skIterator: inc(z.exactMatches, 200)
         case x.state
         of csEmpty, csNoMatch: x = z
         of csMatch: 

compiler/semexprs.nim

@@ -446,11 +446,13 @@ proc analyseIfAddressTakenInCall(c: PContext, n: PNode) =
   
 proc semDirectCallAnalyseEffects(c: PContext, n: PNode,
                                  flags: TExprFlags): PNode =
-  var symflags = {skProc, skMethod, skConverter}
   if efWantIterator in flags:
-    # for ``type countup(1,3)``, see ``tests/ttoseq``.
+    result = semDirectCall(c, n, {skIterator})
-    symflags = {skIterator}
+  elif efInTypeOf in flags:
-  result = semDirectCall(c, n, symflags)
+    # for ``type(countup(1,3))``, see ``tests/ttoseq``.
+    result = semDirectCall(c, n, {skIterator, skProc, skMethod, skConverter})
+  else:
+    result = semDirectCall(c, n, {skProc, skMethod, skConverter})
   if result != nil:
     if result.sons[0].kind != nkSym: 
       InternalError("semDirectCallAnalyseEffects")

compiler/semtypes.nim

@@ -625,23 +625,15 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
     if s.ast == nil: GlobalError(n.info, errCannotInstantiateX, s.name.s)
     result = instGenericContainer(c, n, result)
 
-proc FixupRemainingGenericInvokations(c: PContext, n: PNode, 
-                                      typ: PType): PType =
-  if typ.kind == tyGenericInvokation:
-    nil
-  else:
-    result = typ
-
 proc semTypeNode(c: PContext, n: PNode, prev: PType): PType = 
   result = nil
   if gCmd == cmdIdeTools: suggestExpr(c, n)
   case n.kind
   of nkEmpty: nil
   of nkTypeOfExpr:
-    # for ``type countup(1,3)``, see ``tests/ttoseq``.
+    # for ``type(countup(1,3))``, see ``tests/ttoseq``.
-    # XXX We should find a better solution.
     checkSonsLen(n, 1)
-    result = semExprWithType(c, n.sons[0], {efWantIterator}).typ
+    result = semExprWithType(c, n.sons[0], {efInTypeof}).typ
   of nkPar: 
     if sonsLen(n) == 1: result = semTypeNode(c, n.sons[0], prev)
     else: GlobalError(n.info, errTypeExpected)

compiler/sigmatch.nim

@@ -18,7 +18,7 @@ type
   TCandidateState* = enum 
     csEmpty, csMatch, csNoMatch
   TCandidate* {.final.} = object 
-    exactMatches: int
+    exactMatches*: int
     subtypeMatches: int
     intConvMatches: int      # conversions to int are not as expensive
     convMatches: int

doc/manual.txt

@@ -1460,7 +1460,8 @@ statements always have to be intended::
   complexStmt ::= ifStmt | whileStmt | caseStmt | tryStmt | forStmt
                    | blockStmt | asmStmt
                    | procDecl | iteratorDecl | macroDecl | templateDecl
-                   | constSection | typeSection | whenStmt | varSection
+                   | constSection | letSection 
+                   | typeSection | whenStmt | varSection
 
 
 
@@ -2430,6 +2431,18 @@ be used to get the type of an expression:
   var x = 0
   var y: type(x) # y has type int
 
+If ``type`` is used to determine the result type of a proc/iterator/converter
+call ``c(X)`` (where ``X`` stands for a possibly empty list of arguments), the
+interpretation where ``c`` is an iterator is preferred over the
+other interpretations:
+
+.. code-block:: nimrod
+  import strutils
+  
+  # strutils contains both a ``split`` proc and iterator, but since an
+  # an iterator is the preferred interpretation, `y` has the type ``string``:
+  var y: type("a b c".split)
+
 
 Type constraints
 ~~~~~~~~~~~~~~~~
@@ -3308,6 +3321,7 @@ Memory allocation requires no lock at all! This design easily scales to massive
 multicore processors that will become the norm in the future.
 
 
+
 Thread pragma
 -------------
 

tests/accept/run/ttoseq.nim

@@ -10,3 +10,10 @@ template toSeq*(iter: expr): expr =
 for x in items(toSeq(countup(2, 6))): 
   stdout.write(x)
 
+import strutils
+
+var y: type("a b c".split)
+y = "xzy"
+
+
+