Improve error message layouts

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

diff --git a/compiler/typecheck/TcUnify.lhs b/compiler/typecheck/TcUnify.lhs
index e8fb134..eba9985 100644 (file)
--- a/compiler/typecheck/TcUnify.lhs
+++ b/compiler/typecheck/TcUnify.lhs
@@ -1515,7 +1515,7 @@ notMonoType ty
   = do { ty' <- zonkTcType ty
        ; env0 <- tcInitTidyEnv
        ; let (env1, tidy_ty) = tidyOpenType env0 ty'
-             msg = ptext SLIT("Cannot match a monotype with") <+> ppr tidy_ty
+             msg = ptext SLIT("Cannot match a monotype with") <+> quotes (ppr tidy_ty)
        ; failWithTcM (env1, msg) }
 
 occurCheck tyvar ty