\begin{code}
module DsMonad (
- DsM,
- initDs, returnDs, thenDs, mapDs, listDs,
- mapAndUnzipDs, zipWithDs, foldlDs,
- uniqSMtoDsM,
- newTyVarsDs, cloneTyVarsDs,
+ DsM, mappM, mapAndUnzipM,
+ initDs, returnDs, thenDs, listDs, fixDs, mapAndUnzipDs,
+ foldlDs, foldrDs,
+
+ newTyVarsDs, newLocalName,
duplicateLocalDs, newSysLocalDs, newSysLocalsDs, newUniqueId,
newFailLocalDs,
- getSrcLocDs, putSrcLocDs,
+ getSrcSpanDs, putSrcSpanDs,
getModuleDs,
- getUniqueDs, getUniquesDs,
+ newUnique,
+ UniqSupply, newUniqueSupply,
getDOptsDs,
- dsLookupGlobalId, dsLookupTyCon,
+ dsLookupGlobal, dsLookupGlobalId, dsLookupTyCon, dsLookupDataCon,
DsMetaEnv, DsMetaVal(..), dsLookupMetaEnv, dsExtendMetaEnv,
- dsWarn,
- DsWarnings,
- DsMatchContext(..)
+ -- Warnings
+ DsWarning, dsWarn,
+
+ -- Data types
+ DsMatchContext(..),
+ EquationInfo(..), MatchResult(..), DsWrapper, idWrapper,
+ CanItFail(..), orFail
) where
#include "HsVersions.h"
-import TcHsSyn ( TypecheckedPat, TypecheckedMatchContext, TypecheckedHsExpr )
-import HscTypes ( TyThing(..) )
+import TcRnMonad
+import CoreSyn ( CoreExpr )
+import HsSyn ( HsExpr, HsMatchContext, Pat )
+import TcIface ( tcIfaceGlobal )
+import RdrName ( GlobalRdrEnv )
+import HscTypes ( TyThing(..), TypeEnv, HscEnv,
+ tyThingId, tyThingTyCon, tyThingDataCon, unQualInScope )
import Bag ( emptyBag, snocBag, Bag )
+import DataCon ( DataCon )
import TyCon ( TyCon )
-import ErrUtils ( WarnMsg )
import Id ( mkSysLocal, setIdUnique, Id )
import Module ( Module )
import Var ( TyVar, setTyVarUnique )
import Outputable
-import SrcLoc ( noSrcLoc, SrcLoc )
+import SrcLoc ( noSrcSpan, SrcSpan )
import Type ( Type )
-import UniqSupply ( initUs_, getUniqueUs, getUniquesUs, thenUs, returnUs,
- UniqSM, UniqSupply )
-import Unique ( Unique )
+import UniqSupply ( UniqSupply, uniqsFromSupply )
import Name ( Name, nameOccName )
import NameEnv
import OccName ( occNameFS )
-import CmdLineOpts ( DynFlags )
+import DynFlags ( DynFlags )
+import ErrUtils ( WarnMsg, mkWarnMsg )
+import Bag ( mapBag )
+
+import DATA_IOREF ( newIORef, readIORef )
infixr 9 `thenDs`
\end{code}
+%************************************************************************
+%* *
+ Data types for the desugarer
+%* *
+%************************************************************************
+
+\begin{code}
+data DsMatchContext
+ = DsMatchContext (HsMatchContext Name) [Pat Id] SrcSpan
+ | NoMatchContext
+ deriving ()
+
+data EquationInfo
+ = EqnInfo { eqn_wrap :: DsWrapper, -- Bindings
+ eqn_pats :: [Pat Id], -- The patterns for an eqn
+ eqn_rhs :: MatchResult } -- What to do after match
+
+type DsWrapper = CoreExpr -> CoreExpr
+idWrapper e = e
+
+-- The semantics of (match vs (EqnInfo wrap pats rhs)) is the MatchResult
+-- \fail. wrap (case vs of { pats -> rhs fail })
+-- where vs are not bound by wrap
+
+
+-- A MatchResult is an expression with a hole in it
+data MatchResult
+ = MatchResult
+ CanItFail -- Tells whether the failure expression is used
+ (CoreExpr -> DsM CoreExpr)
+ -- Takes a expression to plug in at the
+ -- failure point(s). The expression should
+ -- be duplicatable!
+
+data CanItFail = CanFail | CantFail
+
+orFail CantFail CantFail = CantFail
+orFail _ _ = CanFail
+\end{code}
+
+
+%************************************************************************
+%* *
+ Monad stuff
+%* *
+%************************************************************************
+
Now the mondo monad magic (yes, @DsM@ is a silly name)---carry around
a @UniqueSupply@ and some annotations, which
presumably include source-file location information:
\begin{code}
-newtype DsM result
- = DsM (DsEnv -> DsWarnings -> UniqSM (result, DsWarnings))
-
-unDsM (DsM x) = x
-
-data DsEnv = DsEnv {
- ds_dflags :: DynFlags,
- ds_globals :: Name -> TyThing, -- Lookup well-known Ids
+type DsM result = TcRnIf DsGblEnv DsLclEnv result
+
+-- Compatibility functions
+fixDs = fixM
+thenDs = thenM
+returnDs = returnM
+listDs = sequenceM
+foldlDs = foldlM
+foldrDs = foldrM
+mapAndUnzipDs = mapAndUnzipM
+
+
+type DsWarning = (SrcSpan, SDoc)
+ -- Not quite the same as a WarnMsg, we have an SDoc here
+ -- and we'll do the print_unqual stuff later on to turn it
+ -- into a Doc.
+
+data DsGblEnv = DsGblEnv {
+ ds_mod :: Module, -- For SCC profiling
+ ds_warns :: IORef (Bag DsWarning), -- Warning messages
+ ds_if_env :: (IfGblEnv, IfLclEnv) -- Used for looking up global,
+ -- possibly-imported things
+ }
+
+data DsLclEnv = DsLclEnv {
ds_meta :: DsMetaEnv, -- Template Haskell bindings
- ds_loc :: SrcLoc, -- to put in pattern-matching error msgs
- ds_mod :: Module -- module: for SCC profiling
+ ds_loc :: SrcSpan -- to put in pattern-matching error msgs
}
-- Inside [| |] brackets, the desugarer looks
data DsMetaVal
= Bound Id -- Bound by a pattern inside the [| |].
-- Will be dynamically alpha renamed.
- -- The Id has type String
+ -- The Id has type THSyntax.Var
- | Splice TypecheckedHsExpr -- These bindings are introduced by
- -- the PendingSplices on a HsBracketOut
-
-instance Monad DsM where
- return = returnDs
- (>>=) = thenDs
-
-type DsWarnings = Bag DsWarning -- The desugarer reports matches which are
- -- completely shadowed or incomplete patterns
-type DsWarning = (Loc, SDoc)
-
-{-# INLINE thenDs #-}
-{-# INLINE returnDs #-}
+ | Splice (HsExpr Id) -- These bindings are introduced by
+ -- the PendingSplices on a HsBracketOut
-- initDs returns the UniqSupply out the end (not just the result)
-initDs :: DynFlags
- -> UniqSupply
- -> (Name -> TyThing)
- -> Module -- module name: for profiling
+initDs :: HscEnv
+ -> Module -> GlobalRdrEnv -> TypeEnv
-> DsM a
- -> (a, DsWarnings)
-
-initDs dflags init_us lookup mod (DsM action)
- = initUs_ init_us (action ds_env emptyBag)
- where
- ds_env = DsEnv { ds_dflags = dflags, ds_globals = lookup,
- ds_loc = noSrcLoc, ds_mod = mod,
- ds_meta = emptyNameEnv }
-
-thenDs :: DsM a -> (a -> DsM b) -> DsM b
-
-thenDs (DsM m1) m2 = DsM( \ env warns ->
- m1 env warns `thenUs` \ (result, warns1) ->
- unDsM (m2 result) env warns1)
-
-returnDs :: a -> DsM a
-returnDs result = DsM (\ env warns -> returnUs (result, warns))
-
-listDs :: [DsM a] -> DsM [a]
-listDs [] = returnDs []
-listDs (x:xs)
- = x `thenDs` \ r ->
- listDs xs `thenDs` \ rs ->
- returnDs (r:rs)
-
-mapDs :: (a -> DsM b) -> [a] -> DsM [b]
-
-mapDs f [] = returnDs []
-mapDs f (x:xs)
- = f x `thenDs` \ r ->
- mapDs f xs `thenDs` \ rs ->
- returnDs (r:rs)
-
-foldlDs :: (a -> b -> DsM a) -> a -> [b] -> DsM a
-
-foldlDs k z [] = returnDs z
-foldlDs k z (x:xs) = k z x `thenDs` \ r ->
- foldlDs k r xs
-
-mapAndUnzipDs :: (a -> DsM (b, c)) -> [a] -> DsM ([b], [c])
-
-mapAndUnzipDs f [] = returnDs ([], [])
-mapAndUnzipDs f (x:xs)
- = f x `thenDs` \ (r1, r2) ->
- mapAndUnzipDs f xs `thenDs` \ (rs1, rs2) ->
- returnDs (r1:rs1, r2:rs2)
-
-zipWithDs :: (a -> b -> DsM c) -> [a] -> [b] -> DsM [c]
-
-zipWithDs f [] ys = returnDs []
-zipWithDs f (x:xs) (y:ys)
- = f x y `thenDs` \ r ->
- zipWithDs f xs ys `thenDs` \ rs ->
- returnDs (r:rs)
+ -> IO (a, Bag WarnMsg)
+
+initDs hsc_env mod rdr_env type_env thing_inside
+ = do { warn_var <- newIORef emptyBag
+ ; let { if_genv = IfGblEnv { if_rec_types = Just (mod, return type_env) }
+ ; if_lenv = mkIfLclEnv mod (ptext SLIT("GHC error in desugarer lookup in") <+> ppr mod)
+ ; gbl_env = DsGblEnv { ds_mod = mod,
+ ds_if_env = (if_genv, if_lenv),
+ ds_warns = warn_var }
+ ; lcl_env = DsLclEnv { ds_meta = emptyNameEnv,
+ ds_loc = noSrcSpan } }
+
+ ; res <- initTcRnIf 'd' hsc_env gbl_env lcl_env thing_inside
+
+ ; warns <- readIORef warn_var
+ ; return (res, mapBag mk_warn warns)
+ }
+ where
+ print_unqual = unQualInScope rdr_env
+
+ mk_warn :: (SrcSpan,SDoc) -> WarnMsg
+ mk_warn (loc,sdoc) = mkWarnMsg loc print_unqual sdoc
\end{code}
+%************************************************************************
+%* *
+ Operations in the monad
+%* *
+%************************************************************************
+
And all this mysterious stuff is so we can occasionally reach out and
grab one or more names. @newLocalDs@ isn't exported---exported
functions are defined with it. The difference in name-strings makes
it easier to read debugging output.
\begin{code}
-uniqSMtoDsM :: UniqSM a -> DsM a
-uniqSMtoDsM u_action = DsM(\ env warns ->
- u_action `thenUs` \ res ->
- returnUs (res, warns))
-
-
-getUniqueDs :: DsM Unique
-getUniqueDs = DsM (\ env warns ->
- getUniqueUs `thenUs` \ uniq ->
- returnUs (uniq, warns))
-
-getUniquesDs :: DsM [Unique]
-getUniquesDs = DsM(\ env warns ->
- getUniquesUs `thenUs` \ uniqs ->
- returnUs (uniqs, warns))
-
-- Make a new Id with the same print name, but different type, and new unique
newUniqueId :: Name -> Type -> DsM Id
newUniqueId id ty
- = getUniqueDs `thenDs` \ uniq ->
+ = newUnique `thenDs` \ uniq ->
returnDs (mkSysLocal (occNameFS (nameOccName id)) uniq ty)
duplicateLocalDs :: Id -> DsM Id
duplicateLocalDs old_local
- = getUniqueDs `thenDs` \ uniq ->
+ = newUnique `thenDs` \ uniq ->
returnDs (setIdUnique old_local uniq)
newSysLocalDs, newFailLocalDs :: Type -> DsM Id
newSysLocalDs ty
- = getUniqueDs `thenDs` \ uniq ->
+ = newUnique `thenDs` \ uniq ->
returnDs (mkSysLocal FSLIT("ds") uniq ty)
-newSysLocalsDs tys = mapDs newSysLocalDs tys
+newSysLocalsDs tys = mappM newSysLocalDs tys
newFailLocalDs ty
- = getUniqueDs `thenDs` \ uniq ->
+ = newUnique `thenDs` \ uniq ->
returnDs (mkSysLocal FSLIT("fail") uniq ty)
-- The UserLocal bit just helps make the code a little clearer
\end{code}
\begin{code}
-cloneTyVarsDs :: [TyVar] -> DsM [TyVar]
-cloneTyVarsDs tyvars
- = getUniquesDs `thenDs` \ uniqs ->
- returnDs (zipWith setTyVarUnique tyvars uniqs)
-
newTyVarsDs :: [TyVar] -> DsM [TyVar]
newTyVarsDs tyvar_tmpls
- = getUniquesDs `thenDs` \ uniqs ->
- returnDs (zipWith setTyVarUnique tyvar_tmpls uniqs)
+ = newUniqueSupply `thenDs` \ uniqs ->
+ returnDs (zipWith setTyVarUnique tyvar_tmpls (uniqsFromSupply uniqs))
\end{code}
We can also reach out and either set/grab location information from
-the @SrcLoc@ being carried around.
+the @SrcSpan@ being carried around.
\begin{code}
getDOptsDs :: DsM DynFlags
-getDOptsDs = DsM(\ env warns -> returnUs (ds_dflags env, warns))
+getDOptsDs = getDOpts
getModuleDs :: DsM Module
-getModuleDs = DsM(\ env warns -> returnUs (ds_mod env, warns))
+getModuleDs = do { env <- getGblEnv; return (ds_mod env) }
-getSrcLocDs :: DsM SrcLoc
-getSrcLocDs = DsM(\ env warns -> returnUs (ds_loc env, warns))
+getSrcSpanDs :: DsM SrcSpan
+getSrcSpanDs = do { env <- getLclEnv; return (ds_loc env) }
-putSrcLocDs :: SrcLoc -> DsM a -> DsM a
-putSrcLocDs new_loc (DsM expr) = DsM(\ env warns ->
- expr (env { ds_loc = new_loc }) warns)
+putSrcSpanDs :: SrcSpan -> DsM a -> DsM a
+putSrcSpanDs new_loc thing_inside = updLclEnv (\ env -> env {ds_loc = new_loc}) thing_inside
-dsWarn :: DsWarning -> DsM ()
-dsWarn warn = DsM(\ env warns -> returnUs ((), warns `snocBag` warn))
+dsWarn :: SDoc -> DsM ()
+dsWarn warn = do { env <- getGblEnv
+ ; loc <- getSrcSpanDs
+ ; updMutVar (ds_warns env) (`snocBag` (loc,msg)) }
+ where
+ msg = ptext SLIT("Warning:") <+> warn
\end{code}
\begin{code}
+dsLookupGlobal :: Name -> DsM TyThing
+-- Very like TcEnv.tcLookupGlobal
+dsLookupGlobal name
+ = do { env <- getGblEnv
+ ; setEnvs (ds_if_env env)
+ (tcIfaceGlobal name) }
+
dsLookupGlobalId :: Name -> DsM Id
-dsLookupGlobalId name = DsM(\ env warns ->
- returnUs (get_id name (ds_globals env name), warns))
+dsLookupGlobalId name
+ = dsLookupGlobal name `thenDs` \ thing ->
+ returnDs (tyThingId thing)
dsLookupTyCon :: Name -> DsM TyCon
-dsLookupTyCon name = DsM(\ env warns ->
- returnUs (get_tycon name (ds_globals env name), warns))
-
-get_id name (AnId id) = id
-get_id name other = pprPanic "dsLookupGlobalId" (ppr name)
-
-get_tycon name (ATyCon tc) = tc
-get_tycon name other = pprPanic "dsLookupTyCon" (ppr name)
+dsLookupTyCon name
+ = dsLookupGlobal name `thenDs` \ thing ->
+ returnDs (tyThingTyCon thing)
+
+dsLookupDataCon :: Name -> DsM DataCon
+dsLookupDataCon name
+ = dsLookupGlobal name `thenDs` \ thing ->
+ returnDs (tyThingDataCon thing)
\end{code}
\begin{code}
dsLookupMetaEnv :: Name -> DsM (Maybe DsMetaVal)
-dsLookupMetaEnv name = DsM(\ env warns -> returnUs (lookupNameEnv (ds_meta env) name, warns))
+dsLookupMetaEnv name = do { env <- getLclEnv; return (lookupNameEnv (ds_meta env) name) }
dsExtendMetaEnv :: DsMetaEnv -> DsM a -> DsM a
-dsExtendMetaEnv menv (DsM m)
- = DsM (\ env warns -> m (env { ds_meta = ds_meta env `plusNameEnv` menv }) warns)
+dsExtendMetaEnv menv thing_inside
+ = updLclEnv (\env -> env { ds_meta = ds_meta env `plusNameEnv` menv }) thing_inside
\end{code}
-%************************************************************************
-%* *
-\subsection{Type synonym @EquationInfo@ and access functions for its pieces}
-%* *
-%************************************************************************
-
-\begin{code}
-data DsMatchContext
- = DsMatchContext TypecheckedMatchContext [TypecheckedPat] SrcLoc
- | NoMatchContext
- deriving ()
-\end{code}
projects / ghc-hetmet.git / blobdiff