Wrap quotes in an error message

b74748ff · Simon Peyton Jones · 301a718b · b74748ff
Commit b74748ff authored Mar 09, 2012 by Simon Peyton Jones
--- a/compiler/typecheck/TcHsType.lhs
+++ b/compiler/typecheck/TcHsType.lhs
@@ -208,7 +208,7 @@ tcHsDeriv hs_ty
       ; let (tvs, pred) = splitForAllTys ty
       ; case getClassPredTys_maybe pred of
           Just (cls, tys) -> return (tvs, cls, tys)
-           Nothing -> failWithTc (ptext (sLit "Illegal deriving item") <+> ppr hs_ty) }
+           Nothing -> failWithTc (ptext (sLit "Illegal deriving item") <+> quotes (ppr hs_ty)) }

 -- Used for 'VECTORISE [SCALAR] instance' declarations
 --