[ATS can now be constrained in the class context
stefanh@cse.unsw.edu.au**20060217173250] {
adddir ./tests/constrained-assoc-types
adddir ./tests/constrained-assoc-types/should_pass
hunk ./Phrac/KindInference.hs 339
-              mapM kiClassConstraints (map class_constraints classes)
hunk ./Phrac/KindInference.hs 341
+              mapM kiClassConstraints (map class_constraints classes)
hunk ./Phrac/Map.hs 168
+
hunk ./Phrac/WellFormedness.hs 124
-              then phasefail ("no instance for superclass " ++ showPpr cid ++
-                              " found when checking instance declaration " ++
+              then phasefail ("cannot entail " ++ showPpr' cc ++
+                              " when checking instance declaration " ++
hunk ./Phrac/WellFormedness.hs 170
-                 else
-                 phasefail ("illegal context for class " ++ showPpr id ++
-                            ": only type variables can be constrained")
+                 else return ()
+{-
+                   phasefail ("illegal context for class " ++ showPpr id ++
+                              ": only type variables can be constrained")
+-}
addfile ./tests/constrained-assoc-types/should_pass/000.out
hunk ./tests/constrained-assoc-types/should_pass/000.out 1
+"1"
addfile ./tests/constrained-assoc-types/should_pass/000.phc
hunk ./tests/constrained-assoc-types/should_pass/000.phc 1
+class Show (T a) => C a where {
+  type T a;
+  get :: a -> T a;
+}
+
+data D = D;
+
+instance Show D where {
+  show _ = "D";
+}
+
+instance C D where {
+  type T D = D;
+  get _ = D;
+}
+
+instance C Int where {
+  type T Int = Int;
+  get i = i;
+}
+
+instance C a => C (List a) where {
+  type T (List a) = T a;
+  get l = case l of
+            Nil -> error "list empty";
+            Cons x _ -> get x;
+          ;
+}
+
+data E = E;
+
+instance C E where {
+  type T E = Int;
+  get _ = 42;
+}
+
+test1 = show (get D);
+test2 = show (get (Cons 1 (Cons 2 Nil)));
+test3 = show (get E);
+main = test2;
+
}