where
bndrs = map fst pairs
-lintCoreExpr (App fun (Type ty))
+lintCoreExpr e@(App fun (Type ty))
-- This is like 'let' for types
-- It's needed when dealing with desugarer output for GADTs. Consider
-- data T = forall a. T a (a->Int) Bool
-- False -> fail)
-- ) a
-- Now the inner case look as though it has incompatible branches.
- = go fun [ty]
+ = addLoc (AnExpr e) $
+ go fun [ty]
where
go (App fun (Type ty)) tys
= do { go fun (ty:tys) }
; lintCoreArgs fun_ty (map Type tys) }
lintCoreExpr e@(App fun arg)
- = do { ty <- lintCoreExpr fun
+ = do { fun_ty <- lintCoreExpr fun
; addLoc (AnExpr e) $
- lintCoreArg ty arg }
+ lintCoreArg fun_ty arg }
lintCoreExpr (Lam var expr)
= addLoc (LambdaBodyOf var) $
do { res <- lintCoreArg ty a
; lintCoreArgs res args }
-lintCoreArg ty a@(Type arg_ty) =
+lintCoreArg fun_ty a@(Type arg_ty) =
do { arg_ty <- lintTy arg_ty
- ; lintTyApp ty arg_ty }
+ ; lintTyApp fun_ty arg_ty }
lintCoreArg fun_ty arg =
-- Make sure function type matches argument
do { arg_ty <- lintCoreExpr arg
- ; let err = mkAppMsg fun_ty arg_ty
+ ; let err = mkAppMsg fun_ty arg_ty arg
; case splitFunTy_maybe fun_ty of
Just (arg,res) ->
do { checkTys arg arg_ty err
addInScopeVars args $ -- Put the args in scope before lintBinder,
-- because the Ids mention the type variables
if isVanillaDataCon con then
- do { mapM lintBinder args
+ do { addLoc (CasePat alt) $ do
+ { mapM lintBinder args
-- FIX! Add check that all args are Ids.
-- Check the pattern
-- Scrutinee type must be a tycon applicn; checked by caller
-- NB: args must be in scope here so that the lintCoreArgs line works.
-- NB: relies on existential type args coming *after* ordinary type args
- ; con_type <- lintTyApps (dataConRepType con) tycon_arg_tys
+ ; con_type <- lintTyApps (dataConRepType con) tycon_arg_tys
-- Can just map Var as we know that this is a vanilla datacon
- ; con_result_ty <- lintCoreArgs con_type (map Var args)
- ; checkTys con_result_ty scrut_ty (mkBadPatMsg con_result_ty scrut_ty)
- -- Check the RHS
+ ; con_result_ty <- lintCoreArgs con_type (map Var args)
+ ; checkTys con_result_ty scrut_ty (mkBadPatMsg con_result_ty scrut_ty)
+ }
+ -- Check the RHS
; checkAltExpr rhs alt_ty }
else -- GADT
; case coreRefineTys in_scope con tvs scrut_ty of {
Nothing -> return () ; -- Alternative is dead code
Just (refine, _) -> updateTvSubstEnv (composeTvSubst in_scope refine subst_env) $
- do { tvs' <- mapM lintTy (mkTyVarTys tvs)
- ; con_type <- lintTyApps (dataConRepType con) tvs'
- ; mapM lintBinder ids -- Lint Ids in the refined world
- ; lintCoreArgs con_type (map Var ids)
+ do { addLoc (CasePat alt) $ do
+ { tvs' <- mapM lintTy (mkTyVarTys tvs)
+ ; con_type <- lintTyApps (dataConRepType con) tvs'
+ ; mapM lintBinder ids -- Lint Ids in the refined world
+ ; lintCoreArgs con_type (map Var ids)
+ }
+
; let refined_alt_ty = substTy (mkTvSubst in_scope refine) alt_ty
-- alt_ty is already an OutType, so don't re-apply
-- the current substitution. But we must apply the
= RhsOf Id -- The variable bound
| LambdaBodyOf Id -- The lambda-binder
| BodyOfLetRec [Id] -- One of the binders
- | CaseAlt CoreAlt -- Pattern of a case alternative
+ | CaseAlt CoreAlt -- Case alternative
+ | CasePat CoreAlt -- *Pattern* of the case alternative
| AnExpr CoreExpr -- Some expression
| ImportedUnfolding SrcLoc -- Some imported unfolding (ToDo: say which)
\end{code}
= (noSrcLoc, text "In the expression:" <+> ppr e)
dumpLoc (CaseAlt (con, args, rhs))
- = (noSrcLoc, text "In a case alternative:" <+> parens (ppr con <+> ppr args))
+ = (noSrcLoc, text "In a case alternative:" <+> parens (ppr con <+> pp_binders args))
+
+dumpLoc (CasePat (con, args, rhs))
+ = (noSrcLoc, text "In the pattern of a case alternative:" <+> parens (ppr con <+> pp_binders args))
dumpLoc (ImportedUnfolding locn)
= (locn, brackets (ptext SLIT("in an imported unfolding")))
------------------------------------------------------
-- Other error messages
-mkAppMsg :: Type -> Type -> Message
-mkAppMsg fun arg
+mkAppMsg :: Type -> Type -> CoreExpr -> Message
+mkAppMsg fun_ty arg_ty arg
= vcat [ptext SLIT("Argument value doesn't match argument type:"),
- hang (ptext SLIT("Fun type:")) 4 (ppr fun),
- hang (ptext SLIT("Arg type:")) 4 (ppr arg)]
+ hang (ptext SLIT("Fun type:")) 4 (ppr fun_ty),
+ hang (ptext SLIT("Arg type:")) 4 (ppr arg_ty),
+ hang (ptext SLIT("Arg:")) 4 (ppr arg)]
mkKindErrMsg :: TyVar -> Type -> Message
mkKindErrMsg tyvar arg_ty