import CoreSyn ( AltCon(..) )
import PrimOp ( primOpType )
import Literal ( literalType )
-import Maybes ( catMaybes )
+import Maybes
import Name ( getSrcLoc )
import ErrUtils ( Message, mkLocMessage )
import Type ( mkFunTys, splitFunTys, splitTyConApp_maybe,
import Util ( zipEqual, equalLength )
import SrcLoc ( srcLocSpan )
import Outputable
-
-infixr 9 `thenL`, `thenL_`, `thenMaybeL`
+import Control.Monad
\end{code}
Checks for
where
lint_binds :: [StgBinding] -> LintM ()
- lint_binds [] = returnL ()
- lint_binds (bind:binds)
- = lintStgBinds bind `thenL` \ binders ->
- addInScopeVars binders (
- lint_binds binds
- )
+ lint_binds [] = return ()
+ lint_binds (bind:binds) = do
+ binders <- lintStgBinds bind
+ addInScopeVars binders $
+ lint_binds binds
\end{code}
\begin{code}
lintStgArg :: StgArg -> LintM (Maybe Type)
-lintStgArg (StgLitArg lit) = returnL (Just (literalType lit))
+lintStgArg (StgLitArg lit) = return (Just (literalType lit))
lintStgArg (StgVarArg v) = lintStgVar v
-lintStgVar v = checkInScope v `thenL_`
- returnL (Just (idType v))
+lintStgVar v = do checkInScope v
+ return (Just (idType v))
\end{code}
\begin{code}
lintStgBinds :: StgBinding -> LintM [Id] -- Returns the binders
-lintStgBinds (StgNonRec binder rhs)
- = lint_binds_help (binder,rhs) `thenL_`
- returnL [binder]
+lintStgBinds (StgNonRec binder rhs) = do
+ lint_binds_help (binder,rhs)
+ return [binder]
lintStgBinds (StgRec pairs)
- = addInScopeVars binders (
- mapL lint_binds_help pairs `thenL_`
- returnL binders
- )
+ = addInScopeVars binders $ do
+ mapM_ lint_binds_help pairs
+ return binders
where
binders = [b | (b,_) <- pairs]
lint_binds_help (binder, rhs)
- = addLoc (RhsOf binder) (
+ = addLoc (RhsOf binder) $ do
-- Check the rhs
- lintStgRhs rhs `thenL` \ maybe_rhs_ty ->
+ maybe_rhs_ty <- lintStgRhs rhs
-- Check binder doesn't have unlifted type
checkL (not (isUnLiftedType binder_ty))
- (mkUnLiftedTyMsg binder rhs) `thenL_`
+ (mkUnLiftedTyMsg binder rhs)
-- Check match to RHS type
- (case maybe_rhs_ty of
- Nothing -> returnL ()
+ case maybe_rhs_ty of
+ Nothing -> return ()
Just rhs_ty -> checkTys binder_ty
rhs_ty
(mkRhsMsg binder rhs_ty)
- ) `thenL_`
- returnL ()
- )
+ return ()
where
binder_ty = idType binder
\end{code}
= lintStgExpr expr
lintStgRhs (StgRhsClosure _ _ _ _ _ binders expr)
- = addLoc (LambdaBodyOf binders) (
- addInScopeVars binders (
- lintStgExpr expr `thenMaybeL` \ body_ty ->
- returnL (Just (mkFunTys (map idType binders) body_ty))
- ))
-
-lintStgRhs (StgRhsCon _ con args)
- = mapMaybeL lintStgArg args `thenL` \ maybe_arg_tys ->
- case maybe_arg_tys of
- Nothing -> returnL Nothing
- Just arg_tys -> checkFunApp con_ty arg_tys (mkRhsConMsg con_ty arg_tys)
+ = addLoc (LambdaBodyOf binders) $
+ addInScopeVars binders $ runMaybeT $ do
+ body_ty <- MaybeT $ lintStgExpr expr
+ return (mkFunTys (map idType binders) body_ty)
+
+lintStgRhs (StgRhsCon _ con args) = runMaybeT $ do
+ arg_tys <- mapM (MaybeT . lintStgArg) args
+ MaybeT $ checkFunApp con_ty arg_tys (mkRhsConMsg con_ty arg_tys)
where
con_ty = dataConRepType con
\end{code}
\begin{code}
lintStgExpr :: StgExpr -> LintM (Maybe Type) -- Nothing if error found
-lintStgExpr (StgLit l) = returnL (Just (literalType l))
+lintStgExpr (StgLit l) = return (Just (literalType l))
-lintStgExpr e@(StgApp fun args)
- = lintStgVar fun `thenMaybeL` \ fun_ty ->
- mapMaybeL lintStgArg args `thenL` \ maybe_arg_tys ->
- case maybe_arg_tys of
- Nothing -> returnL Nothing
- Just arg_tys -> checkFunApp fun_ty arg_tys (mkFunAppMsg fun_ty arg_tys e)
+lintStgExpr e@(StgApp fun args) = runMaybeT $ do
+ fun_ty <- MaybeT $ lintStgVar fun
+ arg_tys <- mapM (MaybeT . lintStgArg) args
+ MaybeT $ checkFunApp fun_ty arg_tys (mkFunAppMsg fun_ty arg_tys e)
-lintStgExpr e@(StgConApp con args)
- = mapMaybeL lintStgArg args `thenL` \ maybe_arg_tys ->
- case maybe_arg_tys of
- Nothing -> returnL Nothing
- Just arg_tys -> checkFunApp con_ty arg_tys (mkFunAppMsg con_ty arg_tys e)
+lintStgExpr e@(StgConApp con args) = runMaybeT $ do
+ arg_tys <- mapM (MaybeT . lintStgArg) args
+ MaybeT $ checkFunApp con_ty arg_tys (mkFunAppMsg con_ty arg_tys e)
where
con_ty = dataConRepType con
-lintStgExpr e@(StgOpApp (StgFCallOp _ _) args res_ty)
- = -- We don't have enough type information to check
+lintStgExpr e@(StgOpApp (StgFCallOp _ _) args res_ty) = runMaybeT $ do
+ -- We don't have enough type information to check
-- the application; ToDo
- mapMaybeL lintStgArg args `thenL` \ maybe_arg_tys ->
- returnL (Just res_ty)
-
-lintStgExpr e@(StgOpApp (StgPrimOp op) args _)
- = mapMaybeL lintStgArg args `thenL` \ maybe_arg_tys ->
- case maybe_arg_tys of
- Nothing -> returnL Nothing
- Just arg_tys -> checkFunApp op_ty arg_tys (mkFunAppMsg op_ty arg_tys e)
+ maybe_arg_tys <- mapM (MaybeT . lintStgArg) args
+ return res_ty
+
+lintStgExpr e@(StgOpApp (StgPrimOp op) args _) = runMaybeT $ do
+ arg_tys <- mapM (MaybeT . lintStgArg) args
+ MaybeT $ checkFunApp op_ty arg_tys (mkFunAppMsg op_ty arg_tys e)
where
op_ty = primOpType op
-lintStgExpr (StgLam _ bndrs _)
- = addErrL (ptext SLIT("Unexpected StgLam") <+> ppr bndrs) `thenL_`
- returnL Nothing
+lintStgExpr (StgLam _ bndrs _) = do
+ addErrL (ptext SLIT("Unexpected StgLam") <+> ppr bndrs)
+ return Nothing
-lintStgExpr (StgLet binds body)
- = lintStgBinds binds `thenL` \ binders ->
- addLoc (BodyOfLetRec binders) (
- addInScopeVars binders (
- lintStgExpr body
- ))
+lintStgExpr (StgLet binds body) = do
+ binders <- lintStgBinds binds
+ addLoc (BodyOfLetRec binders) $
+ addInScopeVars binders $
+ lintStgExpr body
-lintStgExpr (StgLetNoEscape _ _ binds body)
- = lintStgBinds binds `thenL` \ binders ->
- addLoc (BodyOfLetRec binders) (
- addInScopeVars binders (
- lintStgExpr body
- ))
+lintStgExpr (StgLetNoEscape _ _ binds body) = do
+ binders <- lintStgBinds binds
+ addLoc (BodyOfLetRec binders) $
+ addInScopeVars binders $
+ lintStgExpr body
lintStgExpr (StgSCC _ expr) = lintStgExpr expr
-lintStgExpr e@(StgCase scrut _ _ bndr _ alts_type alts)
- = lintStgExpr scrut `thenMaybeL` \ _ ->
-
- (case alts_type of
- AlgAlt tc -> check_bndr tc
- PrimAlt tc -> check_bndr tc
- UbxTupAlt tc -> check_bndr tc
- PolyAlt -> returnL ()
- ) `thenL_`
-
- (trace (showSDoc (ppr e)) $
+lintStgExpr e@(StgCase scrut _ _ bndr _ alts_type alts) = runMaybeT $ do
+ MaybeT $ lintStgExpr scrut
+
+ MaybeT $ liftM Just $
+ case alts_type of
+ AlgAlt tc -> check_bndr tc
+ PrimAlt tc -> check_bndr tc
+ UbxTupAlt tc -> check_bndr tc
+ PolyAlt -> return ()
+
+ MaybeT $ trace (showSDoc (ppr e)) $ do
-- we only allow case of tail-call or primop.
- (case scrut of
- StgApp _ _ -> returnL ()
- StgConApp _ _ -> returnL ()
- StgOpApp _ _ _ -> returnL ()
- other -> addErrL (mkCaseOfCaseMsg e)) `thenL_`
-
- addInScopeVars [bndr] (lintStgAlts alts scrut_ty)
- )
+ case scrut of
+ StgApp _ _ -> return ()
+ StgConApp _ _ -> return ()
+ StgOpApp _ _ _ -> return ()
+ other -> addErrL (mkCaseOfCaseMsg e)
+
+ addInScopeVars [bndr] $
+ lintStgAlts alts scrut_ty
where
scrut_ty = idType bndr
bad_bndr = mkDefltMsg bndr
-> Type -- Type of scrutinee
-> LintM (Maybe Type) -- Type of alternatives
-lintStgAlts alts scrut_ty
- = mapL (lintAlt scrut_ty) alts `thenL` \ maybe_result_tys ->
+lintStgAlts alts scrut_ty = do
+ maybe_result_tys <- mapM (lintAlt scrut_ty) alts
-- Check the result types
case catMaybes (maybe_result_tys) of
- [] -> returnL Nothing
+ [] -> return Nothing
- (first_ty:tys) -> mapL check tys `thenL_`
- returnL (Just first_ty)
+ (first_ty:tys) -> do mapM_ check tys
+ return (Just first_ty)
where
check ty = checkTys first_ty ty (mkCaseAltMsg alts)
lintAlt scrut_ty (DEFAULT, _, _, rhs)
= lintStgExpr rhs
-lintAlt scrut_ty (LitAlt lit, _, _, rhs)
- = checkTys (literalType lit) scrut_ty (mkAltMsg1 scrut_ty) `thenL_`
+lintAlt scrut_ty (LitAlt lit, _, _, rhs) = do
+ checkTys (literalType lit) scrut_ty (mkAltMsg1 scrut_ty)
lintStgExpr rhs
-lintAlt scrut_ty (DataAlt con, args, _, rhs)
- = (case splitTyConApp_maybe scrut_ty of
+lintAlt scrut_ty (DataAlt con, args, _, rhs) = do
+ case splitTyConApp_maybe scrut_ty of
Just (tycon, tys_applied) | isAlgTyCon tycon &&
- not (isNewTyCon tycon) ->
+ not (isNewTyCon tycon) -> do
let
cons = tyConDataCons tycon
arg_tys = dataConInstArgTys con tys_applied
-- This almost certainly does not work for existential constructors
- in
- checkL (con `elem` cons) (mkAlgAltMsg2 scrut_ty con) `thenL_`
+
+ checkL (con `elem` cons) (mkAlgAltMsg2 scrut_ty con)
checkL (equalLength arg_tys args) (mkAlgAltMsg3 con args)
- `thenL_`
- mapL check (zipEqual "lintAlgAlt:stg" arg_tys args) `thenL_`
- returnL ()
+ mapM_ check (zipEqual "lintAlgAlt:stg" arg_tys args)
+ return ()
other ->
addErrL (mkAltMsg1 scrut_ty)
- ) `thenL_`
- addInScopeVars args (
+
+ addInScopeVars args $
lintStgExpr rhs
- )
where
check (ty, arg) = checkTys ty (idType arg) (mkAlgAltMsg4 ty arg)
%************************************************************************
\begin{code}
-type LintM a = [LintLocInfo] -- Locations
- -> IdSet -- Local vars in scope
- -> Bag Message -- Error messages so far
- -> (a, Bag Message) -- Result and error messages (if any)
+newtype LintM a = LintM
+ { unLintM :: [LintLocInfo] -- Locations
+ -> IdSet -- Local vars in scope
+ -> Bag Message -- Error messages so far
+ -> (a, Bag Message) -- Result and error messages (if any)
+ }
data LintLocInfo
= RhsOf Id -- The variable bound
\begin{code}
initL :: LintM a -> Maybe Message
-initL m
+initL (LintM m)
= case (m [] emptyVarSet emptyBag) of { (_, errs) ->
if isEmptyBag errs then
Nothing
Just (vcat (punctuate (text "") (bagToList errs)))
}
-returnL :: a -> LintM a
-returnL r loc scope errs = (r, errs)
+instance Monad LintM where
+ return a = LintM $ \loc scope errs -> (a, errs)
+ (>>=) = thenL
+ (>>) = thenL_
thenL :: LintM a -> (a -> LintM b) -> LintM b
-thenL m k loc scope errs
- = case m loc scope errs of
- (r, errs') -> k r loc scope errs'
+thenL m k = LintM $ \loc scope errs
+ -> case unLintM m loc scope errs of
+ (r, errs') -> unLintM (k r) loc scope errs'
thenL_ :: LintM a -> LintM b -> LintM b
-thenL_ m k loc scope errs
- = case m loc scope errs of
- (_, errs') -> k loc scope errs'
-
-thenMaybeL :: LintM (Maybe a) -> (a -> LintM (Maybe b)) -> LintM (Maybe b)
-thenMaybeL m k loc scope errs
- = case m loc scope errs of
- (Nothing, errs2) -> (Nothing, errs2)
- (Just r, errs2) -> k r loc scope errs2
-
-mapL :: (a -> LintM b) -> [a] -> LintM [b]
-mapL f [] = returnL []
-mapL f (x:xs)
- = f x `thenL` \ r ->
- mapL f xs `thenL` \ rs ->
- returnL (r:rs)
-
-mapMaybeL :: (a -> LintM (Maybe b)) -> [a] -> LintM (Maybe [b])
- -- Returns Nothing if anything fails
-mapMaybeL f [] = returnL (Just [])
-mapMaybeL f (x:xs)
- = f x `thenMaybeL` \ r ->
- mapMaybeL f xs `thenMaybeL` \ rs ->
- returnL (Just (r:rs))
+thenL_ m k = LintM $ \loc scope errs
+ -> case unLintM m loc scope errs of
+ (_, errs') -> unLintM k loc scope errs'
\end{code}
\begin{code}
checkL :: Bool -> Message -> LintM ()
-checkL True msg loc scope errs = ((), errs)
-checkL False msg loc scope errs = ((), addErr errs msg loc)
+checkL True msg = return ()
+checkL False msg = addErrL msg
addErrL :: Message -> LintM ()
-addErrL msg loc scope errs = ((), addErr errs msg loc)
+addErrL msg = LintM $ \loc scope errs -> ((), addErr errs msg loc)
addErr :: Bag Message -> Message -> [LintLocInfo] -> Bag Message
-
addErr errs_so_far msg locs
= errs_so_far `snocBag` mk_msg locs
where
mk_msg [] = msg
addLoc :: LintLocInfo -> LintM a -> LintM a
-addLoc extra_loc m loc scope errs
- = m (extra_loc:loc) scope errs
+addLoc extra_loc m = LintM $ \loc scope errs
+ -> unLintM m (extra_loc:loc) scope errs
addInScopeVars :: [Id] -> LintM a -> LintM a
-addInScopeVars ids m loc scope errs
- = -- We check if these "new" ids are already
+addInScopeVars ids m = LintM $ \loc scope errs
+ -> -- We check if these "new" ids are already
-- in scope, i.e., we have *shadowing* going on.
-- For now, it's just a "trace"; we may make
-- a real error out of it...
-- (if isEmptyVarSet shadowed
-- then id
-- else pprTrace "Shadowed vars:" (ppr (varSetElems shadowed))) $
- m loc (scope `unionVarSet` new_set) errs
+ unLintM m loc (scope `unionVarSet` new_set) errs
\end{code}
Checking function applications: we only check that the type has the
-> Message -- Error messgae
-> LintM (Maybe Type) -- The result type
-checkFunApp fun_ty arg_tys msg loc scope errs
- = cfa res_ty expected_arg_tys arg_tys
- where
+checkFunApp fun_ty arg_tys msg = LintM checkFunApp'
+ where
+ checkFunApp' loc scope errs
+ = cfa res_ty expected_arg_tys arg_tys
+ where
(expected_arg_tys, res_ty) = splitFunTys (dropForAlls fun_ty)
cfa res_ty expected [] -- Args have run out; that's fine
\begin{code}
checkInScope :: Id -> LintM ()
-checkInScope id loc scope errs
- = if isLocalId id && not (id `elemVarSet` scope) then
+checkInScope id = LintM $ \loc scope errs
+ -> if isLocalId id && not (id `elemVarSet` scope) then
((), addErr errs (hsep [ppr id, ptext SLIT("is out of scope")]) loc)
else
((), errs)
checkTys :: Type -> Type -> Message -> LintM ()
-checkTys ty1 ty2 msg loc scope errs
- = -- if (ty1 == ty2) then
+checkTys ty1 ty2 msg = LintM $ \loc scope errs
+ -> -- if (ty1 == ty2) then
((), errs)
-- else ((), addErr errs msg loc)
\end{code}
projects / ghc-hetmet.git / commitdiff