From a3532ac90945bf7c540619f790649ddfbaaf6b2c Mon Sep 17 00:00:00 2001 From: Ian Lynagh Date: Tue, 6 May 2008 19:17:28 +0000 Subject: [PATCH] Make TcDefaults warning-free --- compiler/typecheck/TcDefaults.lhs | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/compiler/typecheck/TcDefaults.lhs b/compiler/typecheck/TcDefaults.lhs index 66064c0..74a1769 100644 --- a/compiler/typecheck/TcDefaults.lhs +++ b/compiler/typecheck/TcDefaults.lhs @@ -5,13 +5,6 @@ \section[TcDefaults]{Typechecking \tr{default} declarations} \begin{code} -{-# OPTIONS -w #-} --- The above warning supression flag is a temporary kludge. --- While working on this module you are encouraged to remove it and fix --- any warnings in the module. See --- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings --- for details - module TcDefaults ( tcDefaults ) where import HsSyn @@ -48,7 +41,7 @@ tcDefaults [] -- one group, only for the next group to ignore them and install -- defaultDefaultTys -tcDefaults [L locn (DefaultDecl [])] +tcDefaults [L _ (DefaultDecl [])] = return (Just []) -- Default declaration specifying no types tcDefaults [L locn (DefaultDecl mono_tys)] @@ -69,6 +62,7 @@ tcDefaults decls@(L locn (DefaultDecl _) : _) failWithTc (dupDefaultDeclErr decls) +tc_default_ty :: [Class] -> LHsType Name -> TcM Type tc_default_ty deflt_clss hs_ty = do { ty <- tcHsSigType DefaultDeclCtxt hs_ty ; checkTc (isTauTy ty) (polyDefErr hs_ty) @@ -85,17 +79,22 @@ check_instance ty cls = do { (_, mb_res) <- tryTc (tcSimplifyDefault [mkClassPred cls [ty]]) ; return (isJust mb_res) } +defaultDeclCtxt :: SDoc defaultDeclCtxt = ptext (sLit "When checking the types in a default declaration") +dupDefaultDeclErr :: [Located (DefaultDecl Name)] -> SDoc dupDefaultDeclErr (L _ (DefaultDecl _) : dup_things) = hang (ptext (sLit "Multiple default declarations")) 4 (vcat (map pp dup_things)) where pp (L locn (DefaultDecl _)) = ptext (sLit "here was another default declaration") <+> ppr locn +dupDefaultDeclErr [] = panic "dupDefaultDeclErr []" +polyDefErr :: LHsType Name -> SDoc polyDefErr ty = hang (ptext (sLit "Illegal polymorphic type in default declaration") <> colon) 4 (ppr ty) +badDefaultTy :: Type -> [Class] -> SDoc badDefaultTy ty deflt_clss = hang (ptext (sLit "The default type") <+> quotes (ppr ty) <+> ptext (sLit "is not an instance of")) 2 (foldr1 (\a b -> a <+> ptext (sLit "or") <+> b) (map (quotes. ppr) deflt_clss)) -- 1.7.10.4