X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FdeSugar%2FDsMonad.lhs;h=f24dee4905257e0dbb16c1c0a4f45fc4e697eca0;hb=28a464a75e14cece5db40f2765a29348273ff2d2;hp=ae58ca9eb6663cb1a38660e4d3316ec3f69d53cc;hpb=495ef8bd9ef30bffe50ea399b91e3ba09646b59a;p=ghc-hetmet.git

diff --git a/ghc/compiler/deSugar/DsMonad.lhs b/ghc/compiler/deSugar/DsMonad.lhs
index ae58ca9..f24dee4 100644
--- a/ghc/compiler/deSugar/DsMonad.lhs
+++ b/ghc/compiler/deSugar/DsMonad.lhs
@@ -5,230 +5,281 @@
 
 \begin{code}
 module DsMonad (
-	DsM,
-	initDs, returnDs, thenDs, andDs, mapDs, listDs,
-	mapAndUnzipDs, zipWithDs, foldlDs,
-	uniqSMtoDsM,
-	newTyVarsDs, cloneTyVarsDs,
-	duplicateLocalDs, newSysLocalDs, newSysLocalsDs,
+	DsM, mappM, mapAndUnzipM,
+	initDs, returnDs, thenDs, listDs, fixDs, mapAndUnzipDs, 
+	foldlDs, foldrDs,
+
+	newTyVarsDs, newLocalName,
+	duplicateLocalDs, newSysLocalDs, newSysLocalsDs, newUniqueId,
 	newFailLocalDs,
-	getSrcLocDs, putSrcLocDs,
+	getSrcSpanDs, putSrcSpanDs,
 	getModuleDs,
-	getUniqueDs,
-	dsLookupGlobalValue,
+	newUnique, 
+	UniqSupply, newUniqueSupply,
+	getDOptsDs,
+	dsLookupGlobal, dsLookupGlobalId, dsLookupTyCon, dsLookupDataCon,
+
+	DsMetaEnv, DsMetaVal(..), dsLookupMetaEnv, dsExtendMetaEnv,
 
-	ValueEnv,
-	dsWarn, 
-	DsWarnings,
-	DsMatchContext(..), DsMatchKind(..)
+	-- Warnings
+	DsWarning, dsWarn, 
+
+	-- Data types
+	DsMatchContext(..),
+	EquationInfo(..), MatchResult(..), DsWrapper, idWrapper,
+	CanItFail(..), orFail
     ) where
 
 #include "HsVersions.h"
 
-import Bag		( emptyBag, snocBag, bagToList, Bag )
-import ErrUtils 	( WarnMsg, pprBagOfErrors )
-import HsSyn		( OutPat )
+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 Id		( mkSysLocal, setIdUnique, Id )
 import Module		( Module )
-import Name		( Name, maybeWiredInIdName )
 import Var		( TyVar, setTyVarUnique )
-import VarEnv
 import Outputable
-import SrcLoc		( noSrcLoc, SrcLoc )
-import TcHsSyn		( TypecheckedPat )
-import TcEnv		( ValueEnv )
+import SrcLoc		( noSrcSpan, SrcSpan )
 import Type             ( Type )
-import UniqSupply	( initUs_, splitUniqSupply, uniqFromSupply, uniqsFromSupply,
-			  UniqSM, UniqSupply )
-import Unique		( Unique )
-import UniqFM		( lookupWithDefaultUFM_Directly )
-import Util		( zipWithEqual )
+import UniqSupply	( UniqSupply, uniqsFromSupply )
+import Name		( Name, nameOccName )
+import NameEnv
+import OccName          ( occNameFS )
+import DynFlags	( DynFlags )
+import ErrUtils		( WarnMsg, mkWarnMsg )
+import Bag		( mapBag )
+
+import DATA_IOREF	( newIORef, readIORef )
 
 infixr 9 `thenDs`
 \end{code}
 
-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}
-type DsM result =
-	UniqSupply
-        -> ValueEnv
-	-> SrcLoc		 -- to put in pattern-matching error msgs
-	-> Module       	 -- module: for SCC profiling
-	-> DsWarnings
-	-> (result, DsWarnings)
-
-type DsWarnings = Bag WarnMsg           -- The desugarer reports matches which are
-					-- completely shadowed or incomplete patterns
-
-{-# INLINE andDs #-}
-{-# INLINE thenDs #-}
-{-# INLINE returnDs #-}
-
--- initDs returns the UniqSupply out the end (not just the result)
-
-initDs  :: UniqSupply
-	-> ValueEnv
-	-> Module   -- module name: for profiling
-	-> DsM a
-	-> (a, DsWarnings)
-
-initDs init_us genv mod action
-  = action init_us genv noSrcLoc mod emptyBag
+%************************************************************************
+%*									*
+		Data types for the desugarer
+%*									*
+%************************************************************************
 
-thenDs :: DsM a -> (a -> DsM b) -> DsM b
-andDs  :: (a -> a -> a) -> DsM a -> DsM a -> DsM a
+\begin{code}
+data DsMatchContext
+  = DsMatchContext (HsMatchContext Name) SrcSpan
+  | NoMatchContext
+  deriving ()
 
-thenDs m1 m2 us genv loc mod warns
-  = case splitUniqSupply us		    of { (s1, s2) ->
-    case (m1 s1 genv loc mod warns)  of { (result, warns1) ->
-    m2 result s2 genv loc mod warns1}}
+data EquationInfo
+  = EqnInfo { eqn_wrap :: DsWrapper,	-- Bindings
+	      eqn_pats :: [Pat Id],    	-- The patterns for an eqn
+	      eqn_rhs  :: MatchResult }	-- What to do after match
 
-andDs combiner m1 m2 us genv loc mod warns
-  = case splitUniqSupply us		    of { (s1, s2) ->
-    case (m1 s1 genv loc mod warns)  of { (result1, warns1) ->
-    case (m2 s2 genv loc mod warns1) of { (result2, warns2) ->
-    (combiner result1 result2, warns2) }}}
+type DsWrapper = CoreExpr -> CoreExpr
+idWrapper e = e
 
-returnDs :: a -> DsM a
-returnDs result us genv loc mod warns = (result, warns)
+-- 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
 
-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]
+-- 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!
 
-mapDs f []     = returnDs []
-mapDs f (x:xs)
-  = f x		`thenDs` \ r  ->
-    mapDs f xs	`thenDs` \ rs ->
-    returnDs (r:rs)
+data CanItFail = CanFail | CantFail
 
-foldlDs :: (a -> b -> DsM a) -> a -> [b] -> DsM a
+orFail CantFail CantFail = CantFail
+orFail _        _	 = CanFail
+\end{code}
 
-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])
+%************************************************************************
+%*									*
+		Monad stuff
+%*									*
+%************************************************************************
 
-mapAndUnzipDs f []     = returnDs ([], [])
-mapAndUnzipDs f (x:xs)
-  = f x		    	`thenDs` \ (r1, r2)  ->
-    mapAndUnzipDs f xs	`thenDs` \ (rs1, rs2) ->
-    returnDs (r1:rs1, r2:rs2)
+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}
+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	   :: SrcSpan		-- to put in pattern-matching error msgs
+     }
+
+-- Inside [| |] brackets, the desugarer looks 
+-- up variables in the DsMetaEnv
+type DsMetaEnv = NameEnv DsMetaVal
+
+data DsMetaVal
+   = Bound Id		-- Bound by a pattern inside the [| |]. 
+			-- Will be dynamically alpha renamed.
+			-- The Id has type THSyntax.Var
+
+   | Splice (HsExpr Id)	-- These bindings are introduced by
+			-- the PendingSplices on a HsBracketOut
 
-zipWithDs :: (a -> b -> DsM c) -> [a] -> [b] -> DsM [c]
+-- initDs returns the UniqSupply out the end (not just the result)
 
-zipWithDs f []	   ys = returnDs []
-zipWithDs f (x:xs) (y:ys)
-  = f x y		`thenDs` \ r  ->
-    zipWithDs f xs ys	`thenDs` \ rs ->
-    returnDs (r:rs)
+initDs  :: HscEnv
+	-> Module -> GlobalRdrEnv -> TypeEnv
+	-> DsM a
+	-> 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}
-newSysLocalDs, newFailLocalDs :: Type -> DsM Id
-newSysLocalDs ty us genv loc mod warns
-  = case uniqFromSupply us of { assigned_uniq ->
-    (mkSysLocal SLIT("ds") assigned_uniq ty, warns) }
+-- Make a new Id with the same print name, but different type, and new unique
+newUniqueId :: Name -> Type -> DsM Id
+newUniqueId id ty
+  = newUnique 	`thenDs` \ uniq ->
+    returnDs (mkSysLocal (occNameFS (nameOccName id)) uniq ty)
 
-newSysLocalsDs tys = mapDs newSysLocalDs tys
+duplicateLocalDs :: Id -> DsM Id
+duplicateLocalDs old_local 
+  = newUnique 	`thenDs` \ uniq ->
+    returnDs (setIdUnique old_local uniq)
 
-newFailLocalDs ty us genv loc mod warns
-  = case uniqFromSupply us of { assigned_uniq ->
-    (mkSysLocal SLIT("fail") assigned_uniq ty, warns) }
-	-- The UserLocal bit just helps make the code a little clearer
+newSysLocalDs, newFailLocalDs :: Type -> DsM Id
+newSysLocalDs ty
+  = newUnique 	`thenDs` \ uniq ->
+    returnDs (mkSysLocal FSLIT("ds") uniq ty)
 
-getUniqueDs :: DsM Unique
-getUniqueDs us genv loc mod warns
-  = case (uniqFromSupply us) of { assigned_uniq ->
-    (assigned_uniq, warns) }
+newSysLocalsDs tys = mappM newSysLocalDs tys
 
-duplicateLocalDs :: Id -> DsM Id
-duplicateLocalDs old_local us genv loc mod warns
-  = case uniqFromSupply us of { assigned_uniq ->
-    (setIdUnique old_local assigned_uniq, warns) }
-
-cloneTyVarsDs :: [TyVar] -> DsM [TyVar]
-cloneTyVarsDs tyvars us genv loc mod warns
-  = case uniqsFromSupply (length tyvars) us of { uniqs ->
-    (zipWithEqual "cloneTyVarsDs" setTyVarUnique tyvars uniqs, warns) }
+newFailLocalDs ty 
+  = newUnique 	`thenDs` \ uniq ->
+    returnDs (mkSysLocal FSLIT("fail") uniq ty)
+	-- The UserLocal bit just helps make the code a little clearer
 \end{code}
 
 \begin{code}
 newTyVarsDs :: [TyVar] -> DsM [TyVar]
-
-newTyVarsDs tyvar_tmpls us genv loc mod warns
-  = case uniqsFromSupply (length tyvar_tmpls) us of { uniqs ->
-    (zipWithEqual "newTyVarsDs" setTyVarUnique tyvar_tmpls uniqs, warns) }
+newTyVarsDs tyvar_tmpls 
+  = 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.
-\begin{code}
-uniqSMtoDsM :: UniqSM a -> DsM a
+the @SrcSpan@ being carried around.
 
-uniqSMtoDsM u_action us genv loc mod warns
-  = (initUs_ us u_action, warns)
+\begin{code}
+getDOptsDs :: DsM DynFlags
+getDOptsDs = getDOpts
 
-getSrcLocDs :: DsM SrcLoc
-getSrcLocDs us genv loc mod warns
-  = (loc, warns)
+getModuleDs :: DsM Module
+getModuleDs = do { env <- getGblEnv; return (ds_mod env) }
 
-putSrcLocDs :: SrcLoc -> DsM a -> DsM a
-putSrcLocDs new_loc expr us genv old_loc mod warns
-  = expr us genv new_loc mod warns
+getSrcSpanDs :: DsM SrcSpan
+getSrcSpanDs = do { env <- getLclEnv; return (ds_loc env) }
 
-dsWarn :: WarnMsg -> DsM ()
-dsWarn warn us genv loc mod warns = ((), warns `snocBag` warn)
+putSrcSpanDs :: SrcSpan -> DsM a -> DsM a
+putSrcSpanDs new_loc thing_inside = updLclEnv (\ env -> env {ds_loc = new_loc}) thing_inside
 
+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}
-getModuleDs :: DsM Module
-getModuleDs us genv loc mod warns = (mod, warns)
+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 
+  = dsLookupGlobal name		`thenDs` \ thing ->
+    returnDs (tyThingId thing)
+
+dsLookupTyCon :: Name -> DsM TyCon
+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}
-dsLookupGlobalValue :: Unique -> DsM Id
-dsLookupGlobalValue key us genv loc mod warns
-  = (lookupWithDefaultUFM_Directly genv def key, warns)
-  where
-    def = pprPanic "tcLookupGlobalValue:" (ppr key)
-\end{code}
-
+dsLookupMetaEnv :: Name -> DsM (Maybe DsMetaVal)
+dsLookupMetaEnv name = do { env <- getLclEnv; return (lookupNameEnv (ds_meta env) name) }
 
-%************************************************************************
-%*									*
-\subsection{Type synonym @EquationInfo@ and access functions for its pieces}
-%*									*
-%************************************************************************
+dsExtendMetaEnv :: DsMetaEnv -> DsM a -> DsM a
+dsExtendMetaEnv menv thing_inside
+  = updLclEnv (\env -> env { ds_meta = ds_meta env `plusNameEnv` menv }) thing_inside
+\end{code}
 
-\begin{code}
-data DsMatchContext
-  = DsMatchContext DsMatchKind [TypecheckedPat] SrcLoc
-  | NoMatchContext
-  deriving ()
 
-data DsMatchKind
-  = FunMatch Id
-  | CaseMatch
-  | LambdaMatch
-  | PatBindMatch
-  | DoBindMatch
-  | ListCompMatch
-  | LetMatch
-  | RecUpdMatch
-  deriving ()
-\end{code}