checkPattern, -- HsExp -> P HsPat
bang_RDR,
checkPatterns, -- SrcLoc -> [HsExp] -> P [HsPat]
- checkDo, -- [Stmt] -> P [Stmt]
- checkMDo, -- [Stmt] -> P [Stmt]
checkMonadComp, -- P (HsStmtContext RdrName)
checkValDef, -- (SrcLoc, HsExp, HsRhs, [HsDecl]) -> P HsDecl
checkValSig, -- (SrcLoc, HsExp, HsRhs, [HsDecl]) -> P HsDecl
HsPredTy p -> extract_pred p acc
HsOpTy ty1 (L loc tv) ty2 -> extract_tv loc tv (extract_lty ty1 (extract_lty ty2 acc))
HsParTy ty -> extract_lty ty acc
- HsNumTy {} -> acc
HsCoreTy {} -> acc -- The type is closed
HsQuasiQuoteTy {} -> acc -- Quasi quotes mention no type variables
HsSpliceTy {} -> acc -- Type splices mention no type variables
get (L _ (FunBind { fun_matches = MatchGroup ms _ })) acc = foldr (get_m.unLoc) acc ms
get _ acc = acc
- get_m (Match (L _ (TypePat ty) : _) _ _) acc = extract_lty ty acc
- get_m _ acc = acc
+ get_m _ acc = acc
\end{code}
check loc _ _ = parseErrorSDoc loc
(text "malformed class assertion:" <+> ppr ty)
----------------------------------------------------------------------------
--- Checking statements in a do-expression
--- We parse do { e1 ; e2 ; }
--- as [ExprStmt e1, ExprStmt e2]
--- checkDo (a) checks that the last thing is an ExprStmt
--- (b) returns it separately
--- same comments apply for mdo as well
-
-checkDo, checkMDo :: SrcSpan -> [LStmt RdrName] -> P ([LStmt RdrName], LHsExpr RdrName)
-
-checkDo = checkDoMDo "a " "'do'"
-checkMDo = checkDoMDo "an " "'mdo'"
-
-checkDoMDo :: String -> String -> SrcSpan -> [LStmt RdrName] -> P ([LStmt RdrName], LHsExpr RdrName)
-checkDoMDo _ nm loc [] = parseErrorSDoc loc (text ("Empty " ++ nm ++ " construct"))
-checkDoMDo pre nm _ ss = do
- check ss
- where
- check [] = panic "RdrHsSyn:checkDoMDo"
- check [L _ (ExprStmt e _ _ _)] = return ([], e)
- check [L l e] = parseErrorSDoc l
- (text ("The last statement in " ++ pre ++ nm ++
- " construct must be an expression:")
- $$ ppr e)
- check (s:ss) = do
- (ss',e') <- check ss
- return ((s:ss'),e')
-
-- -------------------------------------------------------------------------
-- Checking Patterns.
-> do fs <- mapM checkPatField fs
return (ConPatIn c (RecCon (HsRecFields fs dd)))
HsQuasiQuoteE q -> return (QuasiQuotePat q)
--- Generics
- HsType ty -> return (TypePat ty)
_ -> patFail loc e0
placeHolderPunRhs :: LHsExpr RdrName
ppr lhs <+> text "::" <+> ppr ty)
$$ text hint)
where
- hint = if looks_like_foreign lhs
+ hint = if foreign_RDR `looks_like` lhs
then "Perhaps you meant to use -XForeignFunctionInterface?"
- else "Should be of form <variable> :: <type>"
+ else if default_RDR `looks_like` lhs
+ then "Perhaps you meant to use -XDefaultSignatures?"
+ else "Should be of form <variable> :: <type>"
-- A common error is to forget the ForeignFunctionInterface flag
-- so check for that, and suggest. cf Trac #3805
-- Sadly 'foreign import' still barfs 'parse error' because 'import' is a keyword
- looks_like_foreign (L _ (HsVar v)) = v == foreign_RDR
- looks_like_foreign (L _ (HsApp lhs _)) = looks_like_foreign lhs
- looks_like_foreign _ = False
+ looks_like s (L _ (HsVar v)) = v == s
+ looks_like s (L _ (HsApp lhs _)) = looks_like s lhs
+ looks_like _ _ = False
foreign_RDR = mkUnqual varName (fsLit "foreign")
+ default_RDR = mkUnqual varName (fsLit "default")
checkDoAndIfThenElse :: LHsExpr RdrName
-> Bool