Fix scoped type variables for expression type signatures

[ghc-hetmet.git] / compiler / typecheck / TcClassDcl.lhs

diff --git a/compiler/typecheck/TcClassDcl.lhs b/compiler/typecheck/TcClassDcl.lhs
index 9fb530d..9d0fb13 100644 (file)
--- a/compiler/typecheck/TcClassDcl.lhs
+++ b/compiler/typecheck/TcClassDcl.lhs
@@ -7,7 +7,7 @@
 module TcClassDcl ( tcClassSigs, tcClassDecl2, 
                    getGenericInstances, 
                    MethodSpec, tcMethodBind, mkMethodBind, 
-                   tcAddDeclCtxt, badMethodErr
+                   tcAddDeclCtxt, badMethodErr, badATErr, omittedATWarn
                  ) where
 
 #include "HsVersions.h"
@@ -632,6 +632,8 @@ get_generics decl@(ClassDecl {tcdLName = class_name, tcdMeths = def_methods})
        --      f {| a+b |} ... = ...
        --      f {| x+y |} ... = ...
        -- Then at this point we'll have an InstInfo for each
+       --
+       -- The class should be unary, which is why simpleInstInfoTyCon should be ok
     let
        tc_inst_infos :: [(TyCon, InstInfo)]
        tc_inst_infos = [(simpleInstInfoTyCon i, i) | i <- inst_infos]
@@ -759,9 +761,16 @@ badMethodErr clas op
   = hsep [ptext SLIT("Class"), quotes (ppr clas), 
          ptext SLIT("does not have a method"), quotes (ppr op)]
 
+badATErr clas at
+  = hsep [ptext SLIT("Class"), quotes (ppr clas), 
+         ptext SLIT("does not have an associated type"), quotes (ppr at)]
+
 omittedMethodWarn sel_id
   = ptext SLIT("No explicit method nor default method for") <+> quotes (ppr sel_id)
 
+omittedATWarn at
+  = ptext SLIT("No explicit AT declaration for") <+> quotes (ppr at)
+
 badGenericInstance sel_id because
   = sep [ptext SLIT("Can't derive generic code for") <+> quotes (ppr sel_id),
         because]