[svn] r7458: nemerle/trunk/ncc/typing/Typer.n

[nikov]

Log:
Fix bug 937.

Author: nikov
Date: Wed Feb 21 20:53:12 2007
New Revision: 7458

Modified:
   nemerle/trunk/ncc/typing/Typer.n

Modified: nemerle/trunk/ncc/typing/Typer.n
==============================================================================
--- nemerle/trunk/ncc/typing/Typer.n	(original)
+++ nemerle/trunk/ncc/typing/Typer.n	Wed Feb 21 20:53:12 2007
@@ -766,14 +766,32 @@
     }
 
 
+    /** Heuristics to decide how we treat rhs of 'is' operator: type or pattern
+      */
     static CanBeTypeName (expr : PT.PExpr) : bool
     {
       match (expr) {
-        | PT.PExpr.Ref => true
+        | PT.PExpr.Ref
+        | <[ void -> void ]> => true
+
         | <[ $expr . $_ ]>
         | <[ $expr . [ .. $_ ] ]>
-        | <[ $expr [ .. $_ ] ]> =>
+        | <[ $expr [ .. $_ ] ]>
+        | <[ void -> $expr ]>
+        | <[ $expr -> void ]> =>
           CanBeTypeName (expr)
+
+        | <[ $expr1 -> $expr2 ]> =>
+          CanBeTypeName (expr1) && CanBeTypeName (expr2)
+        
+        | <[ @* (.. $exprs) ]> => 
+          if (exprs.Exists ( _ is <[ void ]> )) {
+            Message.Error (expr.Location, $"$expr is not a valid type. Tuple cannot have void elements.");
+            true
+          }
+          else
+            exprs.ForAll (CanBeTypeName)
+
         | _ => false
       }
     }