X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FdeSugar%2FDsMonad.lhs;h=145ba9e37129b11d06594d343a6ec23e94c4ec83;hb=539b572921068dc02cec4c5a71e8516958949336;hp=e47cd57df2d94f0dc2bcf9f162bea8f204583f95;hpb=421819753b3eb4940a26e578ef0e4c5cd31761fa;p=ghc-hetmet.git

diff --git a/compiler/deSugar/DsMonad.lhs b/compiler/deSugar/DsMonad.lhs
index e47cd57..145ba9e 100644
--- a/compiler/deSugar/DsMonad.lhs
+++ b/compiler/deSugar/DsMonad.lhs
@@ -6,19 +6,13 @@
 @DsMonad@: monadery used in desugaring
 
 \begin{code}
-{-# OPTIONS -w #-}
--- The above warning supression flag is a temporary kludge.
--- While working on this module you are encouraged to remove it and fix
--- any warnings in the module. See
---     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
--- for details
-
 module DsMonad (
-	DsM, mappM, mapAndUnzipM,
-	initDs, initDsTc, returnDs, thenDs, listDs, fixDs, mapAndUnzipDs, 
-	foldlDs, foldrDs,
+	DsM, mapM, mapAndUnzipM,
+	initDs, initDsTc, fixDs,
+	foldlM, foldrM, ifOptM,
+	Applicative(..),(<$>),
 
-	newTyVarsDs, newLocalName,
+	newLocalName,
 	duplicateLocalDs, newSysLocalDs, newSysLocalsDs, newUniqueId,
 	newFailLocalDs,
 	getSrcSpanDs, putSrcSpanDs,
@@ -40,8 +34,6 @@ module DsMonad (
 	CanItFail(..), orFail
     ) where
 
-#include "HsVersions.h"
-
 import TcRnMonad
 import CoreSyn
 import HsSyn
@@ -64,10 +56,10 @@ import NameEnv
 import OccName
 import DynFlags
 import ErrUtils
+import MonadUtils
+import FastString
 
 import Data.IORef
-
-infixr 9 `thenDs`
 \end{code}
 
 %************************************************************************
@@ -86,7 +78,11 @@ data EquationInfo
   = EqnInfo { eqn_pats :: [Pat Id],    	-- The patterns for an eqn
 	      eqn_rhs  :: MatchResult }	-- What to do after match
 
+instance Outputable EquationInfo where
+    ppr (EqnInfo pats _) = ppr pats
+
 type DsWrapper = CoreExpr -> CoreExpr
+idDsWrapper :: DsWrapper
 idDsWrapper e = e
 
 -- The semantics of (match vs (EqnInfo wrap pats rhs)) is the MatchResult
@@ -105,8 +101,9 @@ data MatchResult
 
 data CanItFail = CanFail | CantFail
 
+orFail :: CanItFail -> CanItFail -> CanItFail
 orFail CantFail CantFail = CantFail
-orFail _        _	 = CanFail
+orFail _        _        = CanFail
 \end{code}
 
 
@@ -123,14 +120,8 @@ presumably include source-file location information:
 type DsM result = TcRnIf DsGblEnv DsLclEnv result
 
 -- Compatibility functions
+fixDs :: (a -> DsM a) -> DsM a
 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 
@@ -165,7 +156,7 @@ data DsMetaVal
 initDs  :: HscEnv
 	-> Module -> GlobalRdrEnv -> TypeEnv
 	-> DsM a
-	-> IO (Maybe a)
+	-> IO (Messages, Maybe a)
 -- Print errors and warnings, if any arise
 
 initDs hsc_env mod rdr_env type_env thing_inside
@@ -179,7 +170,6 @@ initDs hsc_env mod rdr_env type_env thing_inside
 	-- Display any errors and warnings 
 	-- Note: if -Werror is used, we don't signal an error here.
 	; msgs <- readIORef msg_var
-        ; printErrorsAndWarnings dflags msgs 
 
 	; let final_res | errorsFound dflags msgs = Nothing
 		        | otherwise = case either_res of
@@ -189,7 +179,7 @@ initDs hsc_env mod rdr_env type_env thing_inside
 		-- a UserError exception.  Then it should have put an error
 		-- message in msg_var, so we just discard the exception
 
-	; return final_res }
+	; return (msgs, final_res) }
 
 initDsTc :: DsM a -> TcM a
 initDsTc thing_inside
@@ -199,15 +189,14 @@ initDsTc thing_inside
         ; dflags   <- getDOpts
 	; let type_env = tcg_type_env tcg_env
 	      rdr_env  = tcg_rdr_env tcg_env
-        ; ds_envs <- ioToIOEnv$ mkDsEnvs dflags this_mod rdr_env type_env msg_var
+        ; ds_envs <- liftIO $ mkDsEnvs dflags this_mod rdr_env type_env msg_var
 	; setEnvs ds_envs thing_inside }
 
 mkDsEnvs :: DynFlags -> Module -> GlobalRdrEnv -> TypeEnv -> IORef Messages -> IO (DsGblEnv, DsLclEnv)
 mkDsEnvs dflags mod rdr_env type_env msg_var
-  = do 
-       sites_var <- newIORef []
+  = do -- TODO: unnecessarily monadic
        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)
+               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_unqual = mkPrintUnqualified dflags rdr_env,
@@ -216,7 +205,6 @@ mkDsEnvs dflags mod rdr_env type_env msg_var
 			            ds_loc = noSrcSpan }
 
        return (gbl_env, lcl_env)
-
 \end{code}
 
 %************************************************************************
@@ -233,33 +221,19 @@ it easier to read debugging output.
 \begin{code}
 -- 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)
+newUniqueId id = mkSysLocalM (occNameFS (nameOccName id))
 
 duplicateLocalDs :: Id -> DsM Id
-duplicateLocalDs old_local 
-  = newUnique 	`thenDs` \ uniq ->
-    returnDs (setIdUnique old_local uniq)
+duplicateLocalDs old_local = do
+    uniq <- newUnique
+    return (setIdUnique old_local uniq)
 
 newSysLocalDs, newFailLocalDs :: Type -> DsM Id
-newSysLocalDs ty
-  = newUnique 	`thenDs` \ uniq ->
-    returnDs (mkSysLocal FSLIT("ds") uniq ty)
+newSysLocalDs = mkSysLocalM (fsLit "ds")
+newFailLocalDs = mkSysLocalM (fsLit "fail")
 
-newSysLocalsDs tys = mappM newSysLocalDs tys
-
-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 
-  = newUniqueSupply	`thenDs` \ uniqs ->
-    returnDs (zipWith setTyVarUnique tyvar_tmpls (uniqsFromSupply uniqs))
+newSysLocalsDs :: [Type] -> DsM [Id]
+newSysLocalsDs tys = mapM newSysLocalDs tys
 \end{code}
 
 We can also reach out and either set/grab location information from
@@ -288,9 +262,8 @@ warnDs :: SDoc -> DsM ()
 warnDs warn = do { env <- getGblEnv 
 		 ; loc <- getSrcSpanDs
 		 ; let msg = mkWarnMsg loc (ds_unqual env) 
-				      (ptext SLIT("Warning:") <+> warn)
+				      (ptext (sLit "Warning:") <+> warn)
 		 ; updMutVar (ds_msgs env) (\ (w,e) -> (w `snocBag` msg, e)) }
-	    where
 
 failWithDs :: SDoc -> DsM a
 failWithDs err 
@@ -299,10 +272,12 @@ failWithDs err
 	; let msg = mkErrMsg loc (ds_unqual env) err
 	; updMutVar (ds_msgs env) (\ (w,e) -> (w, e `snocBag` msg))
 	; failM }
-	where
 \end{code}
 
 \begin{code}
+instance MonadThings (IOEnv (Env DsGblEnv DsLclEnv)) where
+    lookupThing = dsLookupGlobal
+
 dsLookupGlobal :: Name -> DsM TyThing
 -- Very like TcEnv.tcLookupGlobal
 dsLookupGlobal name 
@@ -312,23 +287,19 @@ dsLookupGlobal name
 
 dsLookupGlobalId :: Name -> DsM Id
 dsLookupGlobalId name 
-  = dsLookupGlobal name		`thenDs` \ thing ->
-    returnDs (tyThingId thing)
+  = tyThingId <$> dsLookupGlobal name
 
 dsLookupTyCon :: Name -> DsM TyCon
 dsLookupTyCon name
-  = dsLookupGlobal name		`thenDs` \ thing ->
-    returnDs (tyThingTyCon thing)
+  = tyThingTyCon <$> dsLookupGlobal name
 
 dsLookupDataCon :: Name -> DsM DataCon
 dsLookupDataCon name
-  = dsLookupGlobal name		`thenDs` \ thing ->
-    returnDs (tyThingDataCon thing)
+  = tyThingDataCon <$> dsLookupGlobal name
 
 dsLookupClass :: Name -> DsM Class
 dsLookupClass name
-  = dsLookupGlobal name         `thenDs` \ thing ->
-    returnDs (tyThingClass thing)
+  = tyThingClass <$> dsLookupGlobal name
 \end{code}
 
 \begin{code}