fix #544

compiler/sigmatch.nim

@@ -629,6 +629,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
     elif skipTypes(a, {tyRange}).kind == f.kind: result = isSubtype
   of tyRange:
     if a.kind == f.kind:
+      if f.base.kind == tyNone: return isGeneric
       result = typeRel(c, base(f), base(a))
       # bugfix: accept integer conversions here
       #if result < isGeneric: result = isNone
@@ -948,7 +949,7 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
           else:
             internalAssert a.sons != nil and a.sons.len > 0
             c.typedescMatched = true
-            result = typeRel(c, f.base, a.base)
+            result = typeRel(c, f.base, a.skipTypes({tyGenericParam, tyTypeDesc}))
         else:
           result = isNone
       else:

tests/misc/tvarious.nim

@@ -51,17 +51,17 @@ while i < s.len:
 write(stdout, "Du heißt " & s)
 
 # bug #544
-when false:
-  # yay, fails again
-  type Bar [T; I:range] = array[I, T]
-  proc foo*[T; I:range](a, b: Bar[T, I]): Bar[T, I] =
-    when len(a) != 3: 
-      # Error: constant expression expected
-      {.fatal:"Dimensions have to be 3".}
-    #...
-  block:
-    var a, b: Bar[int, 0..2]
-    discard foo(a, b)
+
+# yay, fails again
+type Bar [T; I:range] = array[I, T]
+proc foo*[T; I:range](a, b: Bar[T, I]): Bar[T, I] =
+  when len(a) != 3:
+    # Error: constant expression expected
+    {.fatal:"Dimensions have to be 3".}
+  #...
+block:
+  var a, b: Bar[int, range[0..2]]
+  discard foo(a, b)
 
 # bug #1788