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
+ checkDoAndIfThenElse,
parseError,
parseErrorSDoc,
) where
import TypeRep ( Kind )
import RdrName ( RdrName, isRdrTyVar, isRdrTc, mkUnqual, rdrNameOcc,
isRdrDataCon, isUnqual, getRdrName, setRdrNameSpace )
+import Name ( Name )
import BasicTypes ( maxPrecedence, Activation(..), RuleMatchInfo,
- InlinePragma(..) )
+ InlinePragma(..), InlineSpec(..) )
import Lexer
import TysWiredIn ( unitTyCon )
import ForeignCall
import Maybes
import Control.Applicative ((<$>))
+import Control.Monad
import Text.ParserCombinators.ReadP as ReadP
import Data.List ( nubBy )
import Data.Char
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
HsKindSig ty _ -> extract_lty ty acc
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}
\begin{code}
mkClassDecl :: SrcSpan
- -> Located (LHsContext RdrName, LHsType RdrName)
+ -> Located (Maybe (LHsContext RdrName), LHsType RdrName)
-> Located [Located (FunDep RdrName)]
-> Located (OrdList (LHsDecl RdrName))
-> P (LTyClDecl RdrName)
-mkClassDecl loc (L _ (cxt, tycl_hdr)) fds where_cls
+mkClassDecl loc (L _ (mcxt, tycl_hdr)) fds where_cls
= do { let (binds, sigs, ats, docs) = cvBindsAndSigs (unLoc where_cls)
+ ; let cxt = fromMaybe (noLoc []) mcxt
; (cls, tparams) <- checkTyClHdr tycl_hdr
; tyvars <- checkTyVars tparams -- Only type vars allowed
; checkKindSigs ats
mkTyData :: SrcSpan
-> NewOrData
-> Bool -- True <=> data family instance
- -> Located (LHsContext RdrName, LHsType RdrName)
+ -> Located (Maybe (LHsContext RdrName), LHsType RdrName)
-> Maybe Kind
-> [LConDecl RdrName]
-> Maybe [LHsType RdrName]
-> P (LTyClDecl RdrName)
-mkTyData loc new_or_data is_family (L _ (cxt, tycl_hdr)) ksig data_cons maybe_deriv
+mkTyData loc new_or_data is_family (L _ (mcxt, tycl_hdr)) ksig data_cons maybe_deriv
= do { (tc, tparams) <- checkTyClHdr tycl_hdr
+ ; checkDatatypeContext mcxt
+ ; let cxt = fromMaybe (noLoc []) mcxt
; (tyvars, typats) <- checkTParams is_family tparams
; return (L loc (TyData { tcdND = new_or_data, tcdCtxt = cxt, tcdLName = tc,
tcdTyVars = tyvars, tcdTyPats = typats,
-- f x then behave as if she'd written $(f x)
-- ie a SpliceD
mkTopSpliceDecl (L _ (HsQuasiQuoteE qq)) = QuasiQuoteD qq
-mkTopSpliceDecl (L _ (HsSpliceE (HsSplice _ expr))) = SpliceD (SpliceDecl expr)
-mkTopSpliceDecl other_expr = SpliceD (SpliceDecl other_expr)
+mkTopSpliceDecl (L _ (HsSpliceE (HsSplice _ expr))) = SpliceD (SpliceDecl expr Explicit)
+mkTopSpliceDecl other_expr = SpliceD (SpliceDecl other_expr Implicit)
\end{code}
%************************************************************************
split (L _ (HsAppTy t u)) ts = split t (u : ts)
split (L l (HsTyVar tc)) ts = do data_con <- tyConToDataCon l tc
return (data_con, mk_rest ts)
- split (L l _) _ = parseError l "parse error in data/newtype declaration"
+ split (L l _) _ = parseErrorSDoc l (text "parse error in constructor in data/newtype declaration:" <+> ppr ty)
mk_rest [L _ (HsRecTy flds)] = RecCon flds
mk_rest ts = PrefixCon ts
check (HsOpTy t1 (L _ tc) t2) args | isRdrTc tc = done tc (t1:t2:args)
check (HsAppTy l r) args = check (unLoc l) (r:args)
check (HsParTy t) args = check (unLoc t) args
- check _ _ = parseError spn "Malformed instance header"
+ check _ _ = parseErrorSDoc spn (text "Malformed instance header:" <+> ppr ty)
done tc args = return (L spn (HsPredTy (HsClassP tc args)))
| isRdrTyVar tv = return (L l (KindedTyVar tv k))
chk (L l (HsTyVar tv))
| isRdrTyVar tv = return (L l (UserTyVar tv placeHolderKind))
- chk (L l _) =
- parseError l "Type found where type variable expected"
+ chk t@(L l _) =
+ parseErrorSDoc l (text "Type found:" <+> ppr t
+ $$ text "where type variable expected, in:" <+>
+ sep (map (pprParendHsType . unLoc) tparms))
+
+checkDatatypeContext :: Maybe (LHsContext RdrName) -> P ()
+checkDatatypeContext Nothing = return ()
+checkDatatypeContext (Just (L loc c))
+ = do allowed <- extension datatypeContextsEnabled
+ unless allowed $
+ parseErrorSDoc loc
+ (text "Illegal datatype context (use -XDatatypeContexts):" <+>
+ pprHsContext c)
checkTyClHdr :: LHsType RdrName
-> P (Located RdrName, -- the head symbol (type or class name)
| isRdrTc tc = return (ltc, t1:t2:acc)
go _ (HsParTy ty) acc = goL ty acc
go _ (HsAppTy t1 t2) acc = goL t1 (t2:acc)
- go l _ _ = parseError l "Malformed head of type or class declaration"
+ go l _ _ = parseErrorSDoc l (text "Malformed head of type or class declaration:" <+> ppr ty)
-- Check that associated type declarations of a class are all kind signatures.
--
| isFamilyDecl tydecl
|| isSynDecl tydecl = return ()
| otherwise =
- parseError l "Type declaration in a class must be a kind signature or synonym default"
+ parseErrorSDoc l (text "Type declaration in a class must be a kind signature or synonym default:" $$ ppr tydecl)
checkContext :: LHsType RdrName -> P (LHsContext RdrName)
checkContext (L l t)
check _loc (HsAppTy l r) args = checkl l (r:args)
check _loc (HsOpTy l (L loc tc) r) args = check loc (HsTyVar tc) (l:r:args)
check _loc (HsParTy t) args = checkl t args
- check loc _ _ = parseError loc
- "malformed class assertion"
-
----------------------------------------------------------------------------
--- 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 [] = parseError loc ("Empty " ++ nm ++ " construct")
-checkDoMDo pre nm _ ss = do
- check ss
- where
- check [] = panic "RdrHsSyn:checkDoMDo"
- check [L _ (ExprStmt e _ _)] = return ([], e)
- check [L l _] = parseError l ("The last statement in " ++ pre ++ nm ++
- " construct must be an expression")
- check (s:ss) = do
- (ss',e') <- check ss
- return ((s:ss'),e')
+ check loc _ _ = parseErrorSDoc loc
+ (text "malformed class assertion:" <+> ppr ty)
-- -------------------------------------------------------------------------
-- Checking Patterns.
= do { pState <- getPState
; p <- checkAPat (dflags pState) loc e
; return (L loc p) }
-checkPat loc _ _
- = patFail loc
+checkPat loc e _
+ = patFail loc (unLoc e)
checkAPat :: DynFlags -> SrcSpan -> HsExpr RdrName -> P (Pat RdrName)
-checkAPat dynflags loc e = case e of
+checkAPat dynflags loc e0 = case e0 of
EWildPat -> return (WildPat placeHolderType)
HsVar x -> return (VarPat x)
HsLit l -> return (LitPat l)
| bang == bang_RDR
-> do { bang_on <- extension bangPatEnabled
; if bang_on then checkLPat e >>= (return . BangPat)
- else parseError loc "Illegal bang-pattern (use -XBangPatterns)" }
+ else parseErrorSDoc loc (text "Illegal bang-pattern (use -XBangPatterns):" $$ ppr e0) }
ELazyPat e -> checkLPat e >>= (return . LazyPat)
EAsPat n e -> checkLPat e >>= (return . AsPat n)
-- n+k patterns
OpApp (L nloc (HsVar n)) (L _ (HsVar plus)) _
(L _ (HsOverLit lit@(OverLit {ol_val = HsIntegral {}})))
- | dopt Opt_NPlusKPatterns dynflags && (plus == plus_RDR)
+ | xopt Opt_NPlusKPatterns dynflags && (plus == plus_RDR)
-> return (mkNPlusKPat (L nloc n) lit)
OpApp l op _fix r -> do l <- checkLPat l
case op of
L cl (HsVar c) | isDataOcc (rdrNameOcc c)
-> return (ConPatIn (L cl c) (InfixCon l r))
- _ -> patFail loc
+ _ -> patFail loc e0
HsPar e -> checkLPat e >>= (return . ParPat)
ExplicitList _ es -> do ps <- mapM checkLPat es
ExplicitTuple es b
| all tupArgPresent es -> do ps <- mapM checkLPat [e | Present e <- es]
return (TuplePat ps b placeHolderType)
- | otherwise -> parseError loc "Illegal tuple section in pattern"
+ | otherwise -> parseErrorSDoc loc (text "Illegal tuple section in pattern:" $$ ppr e0)
RecordCon c _ (HsRecFields fs dd)
-> 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
+ _ -> patFail loc e0
placeHolderPunRhs :: LHsExpr RdrName
-- The RHS of a punned record field will be filled in by the renamer
checkPatField fld = do { p <- checkLPat (hsRecFieldArg fld)
; return (fld { hsRecFieldArg = p }) }
-patFail :: SrcSpan -> P a
-patFail loc = parseError loc "Parse error in pattern"
+patFail :: SrcSpan -> HsExpr RdrName -> P a
+patFail loc e = parseErrorSDoc loc (text "Parse error in pattern:" <+> ppr e)
---------------------------------------------------------------------------
checkValSig (L l (HsVar v)) ty
| isUnqual v && not (isDataOcc (rdrNameOcc v))
= return (TypeSig (L l v) ty)
-checkValSig lhs@(L l _) _
- | looks_like_foreign lhs
- = parseError l "Invalid type signature; perhaps you meant to use -XForeignFunctionInterface?"
- | otherwise
- = parseError l "Invalid type signature: should be of form <variable> :: <type>"
+checkValSig lhs@(L l _) ty
+ = parseErrorSDoc l ((text "Invalid type signature:" <+>
+ ppr lhs <+> text "::" <+> ppr ty)
+ $$ text hint)
where
+ hint = if foreign_RDR `looks_like` lhs
+ then "Perhaps you meant to use -XForeignFunctionInterface?"
+ else if default_RDR `looks_like` lhs
+ then "Perhaps you meant to use -XDefaultSignatures?"
+ else "Should be of form <variable> :: <type>"
-- A common error is to forget the ForeignFunctionInterface flag
-- so check for that, and suggest. cf Trac #3805
-- Sadly 'foreign import' still barfs 'parse error' because 'import' is a keyword
- looks_like_foreign (L _ (HsVar v)) = v == foreign_RDR
- looks_like_foreign (L _ (HsApp lhs _)) = looks_like_foreign lhs
- looks_like_foreign _ = False
+ looks_like s (L _ (HsVar v)) = v == s
+ looks_like s (L _ (HsApp lhs _)) = looks_like s lhs
+ looks_like _ _ = False
foreign_RDR = mkUnqual varName (fsLit "foreign")
+ default_RDR = mkUnqual varName (fsLit "default")
+
+checkDoAndIfThenElse :: LHsExpr RdrName
+ -> Bool
+ -> LHsExpr RdrName
+ -> Bool
+ -> LHsExpr RdrName
+ -> P ()
+checkDoAndIfThenElse guardExpr semiThen thenExpr semiElse elseExpr
+ | semiThen || semiElse
+ = do pState <- getPState
+ unless (xopt Opt_DoAndIfThenElse (dflags pState)) $ do
+ parseErrorSDoc (combineLocs guardExpr elseExpr)
+ (text "Unexpected semi-colons in conditional:"
+ $$ nest 4 expr
+ $$ text "Perhaps you meant to use -XDoAndIfThenElse?")
+ | otherwise = return ()
+ where pprOptSemi True = semi
+ pprOptSemi False = empty
+ expr = text "if" <+> ppr guardExpr <> pprOptSemi semiThen <+>
+ text "then" <+> ppr thenExpr <> pprOptSemi semiElse <+>
+ text "else" <+> ppr elseExpr
\end{code}
_ -> return Nothing }
go _ _ = return Nothing
+
+---------------------------------------------------------------------------
+-- Check for monad comprehensions
+--
+-- If the flag MonadComprehensions is set, return a `MonadComp' context,
+-- otherwise use the usual `ListComp' context
+
+checkMonadComp :: P (HsStmtContext Name)
+checkMonadComp = do
+ pState <- getPState
+ return $ if xopt Opt_MonadComprehensions (dflags pState)
+ then MonadComp
+ else ListComp
+
---------------------------------------------------------------------------
-- Miscellaneous utilities
checkPrecP :: Located Int -> P Int
checkPrecP (L l i)
| 0 <= i && i <= maxPrecedence = return i
- | otherwise = parseError l "Precedence out of range"
+ | otherwise
+ = parseErrorSDoc l (text ("Precedence out of range: " ++ show i))
mkRecConstrOrUpdate
:: LHsExpr RdrName
mkRecConstrOrUpdate (L l (HsVar c)) _ (fs,dd) | isRdrDataCon c
= return (RecordCon (L l c) noPostTcExpr (mk_rec_fields fs dd))
mkRecConstrOrUpdate exp loc (fs,dd)
- | null fs = parseError loc "Empty record update"
+ | null fs = parseErrorSDoc loc (text "Empty record update of:" <+> ppr exp)
| otherwise = return (RecordUpd exp (mk_rec_fields fs dd) [] [] [])
mk_rec_fields :: [HsRecField id arg] -> Bool -> HsRecFields id arg
mk_rec_fields fs False = HsRecFields { rec_flds = fs, rec_dotdot = Nothing }
mk_rec_fields fs True = HsRecFields { rec_flds = fs, rec_dotdot = Just (length fs) }
-mkInlinePragma :: Maybe Activation -> RuleMatchInfo -> Bool -> InlinePragma
+mkInlinePragma :: (InlineSpec, RuleMatchInfo) -> Maybe Activation -> InlinePragma
-- The Maybe is because the user can omit the activation spec (and usually does)
-mkInlinePragma mb_act match_info inl
+mkInlinePragma (inl, match_info) mb_act
= InlinePragma { inl_inline = inl
, inl_sat = Nothing
, inl_act = act
where
act = case mb_act of
Just act -> act
- Nothing | inl -> AlwaysActive
- | otherwise -> NeverActive
- -- If no specific phase is given then:
- -- NOINLINE => NeverActive
- -- INLINE => Active
+ Nothing -> -- No phase specified
+ case inl of
+ NoInline -> NeverActive
+ _other -> AlwaysActive
-----------------------------------------------------------------------------
-- utilities for foreign declarations
| otherwise = do
case parseCImport cconv safety (mkExtName (unLoc v)) (unpackFS entity) of
- Nothing -> parseError loc "Malformed entity string"
+ Nothing -> parseErrorSDoc loc (text "Malformed entity string")
Just importSpec -> return (ForD (ForeignImport v ty importSpec))
-- the string "foo" is ambigous: either a header or a C identifier. The
projects / ghc-hetmet.git / blobdiff