[svn] r7469: vs-plugin/trunk/Nemerle.Compiler.Utils/Utils.n

[IT]

Log:
Fixed type recursion (bug #912).

Author: IT
Date: Thu Feb 22 22:40:01 2007
New Revision: 7469

Modified:
   vs-plugin/trunk/Nemerle.Compiler.Utils/Utils.n

Modified: vs-plugin/trunk/Nemerle.Compiler.Utils/Utils.n
==============================================================================
--- vs-plugin/trunk/Nemerle.Compiler.Utils/Utils.n	(original)
+++ vs-plugin/trunk/Nemerle.Compiler.Utils/Utils.n	Thu Feb 22 22:40:01 2007
@@ -161,26 +161,56 @@
 
     public static ToDisplayString(this t : TyVar) : string
     {
-      GetNameFromType(t);
+      ToDisplayString(t, SCG.Dictionary())
     }
 
     public static ToDisplayString(this t : MType) : string
     {
-      GetNameFromType(t);
+      ToDisplayString(t, SCG.Dictionary())
     }
 
     public static GetNameFromType (t : TyVar) : string
     {
-      | mType is MType => GetNameFromType(mType)
+      GetNameFromType(t, SCG.Dictionary())
+    }
+
+    public static GetNameFromType (t : MType) : string
+    {
+      GetNameFromType(t, SCG.Dictionary())
+    }
+
+    private static ToDisplayString(t : TyVar, types : SCG.Dictionary[MType,int]) : string
+    {
+      GetNameFromType(t, types);
+    }
+
+    private static ToDisplayString(t : MType, types : SCG.Dictionary[MType,int]) : string
+    {
+      GetNameFromType(t, types);
+    }
+
+    private static GetNameFromType (t : TyVar, types : SCG.Dictionary[MType,int]) : string
+    {
+      match (t)
+      {
+        | mType is MType => GetNameFromType(mType, types)
       | x => 
         match (x.UpperBound)
         {
-          | Some(mType) => GetNameFromType(mType)
+            | Some(mType) => GetNameFromType(mType, types)
           | _ => "<unknown>"
         }
     }
+    }
 
-    public static GetNameFromType (t : MType) : string
+    private static GetNameFromType (t : MType, types : SCG.Dictionary[MType,int]) : string
+    {
+      when (types.ContainsKey(t))
+        return "<error: cyclic type found>";
+
+      types.Add(t, 0);
+
+      match (t)
     {
       | Class as c => 
         mutable name = Completion.ReplaceSpecialName(c.tycon.FrameworkTypeName);
@@ -190,7 +220,7 @@
           name += "[";
           
           foreach (x in c.args)
-            name += GetNameFromType (x) + ", ";
+              name += GetNameFromType (x, types) + ", ";
 
           name = name.Trim(',', ' ') + "]";
         }
@@ -203,15 +233,16 @@
         if (fromTy : object == t || toTy : object == t)
           "<error: cyclic type found>"
         else
-          GetNameFromType(fromTy) + " -> " + GetNameFromType(toTy)
+            GetNameFromType(fromTy) + " -> " + GetNameFromType(toTy, types)
 
-      | Tuple as tuple => tuple.args.Map(ToDisplayString).ToString(" * ")
-      | Array as a => "array[" + GetNameFromType(a.t.Fix()) + "]"
+        | Tuple as tuple => tuple.args.Map(ToDisplayString(_, types)).ToString(" * ")
+        | Array as a => "array[" + GetNameFromType(a.t.Fix(), types) + "]"
       | Void => "void"
-      | Ref as rf => "ref " + GetNameFromType (rf.t.Fix())
-      | Out as ut => "out " + GetNameFromType (ut.t.Fix())
+        | Ref as rf => "ref " + GetNameFromType (rf.t.Fix(), types)
+        | Out as ut => "out " + GetNameFromType (ut.t.Fix(), types)
       | Intersection(types) => $"one of $types"
     }
+    }
 
     public static GetGlyphIndex(this member : IMember) : int
     {