[project @ 1998-08-14 12:09:33 by sof]

[ghc-hetmet.git] / ghc / compiler / deSugar / DsMonad.lhs

diff --git a/ghc/compiler/deSugar/DsMonad.lhs b/ghc/compiler/deSugar/DsMonad.lhs
index 3428be6..bea0247 100644 (file)
--- a/ghc/compiler/deSugar/DsMonad.lhs
+++ b/ghc/compiler/deSugar/DsMonad.lhs
@@ -4,52 +4,43 @@
 \section[DsMonad]{@DsMonad@: monadery used in desugaring}
 
 \begin{code}
-#include "HsVersions.h"
-
 module DsMonad (
-       SYN_IE(DsM),
+       DsM,
        initDs, returnDs, thenDs, andDs, mapDs, listDs,
-       mapAndUnzipDs, zipWithDs,
+       mapAndUnzipDs, zipWithDs, foldlDs,
        uniqSMtoDsM,
        newTyVarsDs, cloneTyVarsDs,
        duplicateLocalDs, newSysLocalDs, newSysLocalsDs,
        newFailLocalDs,
        getSrcLocDs, putSrcLocDs,
-       getModuleAndGroupDs,
+       getModuleAndGroupDs, getUniqueDs,
        extendEnvDs, lookupEnvDs, 
-       SYN_IE(DsIdEnv),
-
-       dsShadowWarn, dsIncompleteWarn,
-       SYN_IE(DsWarnings),
-       DsMatchContext(..), DsMatchKind(..), pprDsWarnings,
-        DsWarnFlavour -- Nuke with 1.4
+       DsIdEnv,
 
+       dsWarn, 
+       DsWarnings,
+       DsMatchContext(..), DsMatchKind(..), pprDsWarnings
     ) where
 
-IMP_Ubiq()
+#include "HsVersions.h"
 
 import Bag             ( emptyBag, snocBag, bagToList, Bag )
-import BasicTypes       ( SYN_IE(Module) )
-import CmdLineOpts     ( opt_PprUserLength )
-import CoreSyn         ( SYN_IE(CoreExpr) )
-import CoreUtils       ( substCoreExpr )
+import BasicTypes       ( Module )
+import ErrUtils        ( WarnMsg )
 import HsSyn           ( OutPat )
-import Id              ( mkSysLocal, mkIdWithNewUniq,
-                         lookupIdEnv, growIdEnvList, GenId, SYN_IE(IdEnv),
-                         SYN_IE(Id)
+import MkId            ( mkSysLocal )
+import Id              ( mkIdWithNewUniq,
+                         lookupIdEnv, growIdEnvList, IdEnv, Id
                        )
-import PprType         ( GenType, GenTyVar )
-import Outputable      ( pprQuote, Outputable(..), PprStyle(..) )
-import Pretty
+import Outputable
 import SrcLoc          ( noSrcLoc, SrcLoc )
-import TcHsSyn         ( SYN_IE(TypecheckedPat) )
-import Type             ( SYN_IE(Type) )
-import TyVar           ( nullTyVarEnv, cloneTyVar, GenTyVar{-instance Eq-}, SYN_IE(TyVar) )
-import Unique          ( Unique{-instances-} )
+import TcHsSyn         ( TypecheckedPat )
+import Type             ( Type )
+import TyVar           ( cloneTyVar, TyVar )
 import UniqSupply      ( splitUniqSupply, getUnique, getUniques,
-                         mapUs, thenUs, returnUs, SYN_IE(UniqSM),
-                         UniqSupply )
-import Util            ( assoc, mapAccumL, zipWithEqual, panic )
+                         UniqSM, UniqSupply )
+import Unique          ( Unique )                        
+import Util            ( zipWithEqual, panic )
 
 infixr 9 `thenDs`
 \end{code}
@@ -66,8 +57,7 @@ type DsM result =
        -> DsWarnings
        -> (result, DsWarnings)
 
-type DsWarnings = Bag (DsWarnFlavour, DsMatchContext)
-                                       -- The desugarer reports matches which are
+type DsWarnings = Bag WarnMsg           -- The desugarer reports matches which are
                                        -- completely shadowed or incomplete patterns
 
 type Group = FAST_STRING
@@ -119,6 +109,13 @@ mapDs f (x:xs)
     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 ([], [])
@@ -151,6 +148,11 @@ newSysLocalDs          = newLocalDs SLIT("ds")
 newSysLocalsDs tys  = mapDs (newLocalDs SLIT("ds")) tys
 newFailLocalDs     = newLocalDs SLIT("fail")
 
+getUniqueDs :: DsM Unique
+getUniqueDs us loc mod_and_grp env warns
+  = case (getUnique us) of { assigned_uniq ->
+    (assigned_uniq, warns) }
+
 duplicateLocalDs :: Id -> DsM Id
 duplicateLocalDs old_local us loc mod_and_grp env warns
   = case (getUnique us) of { assigned_uniq ->
@@ -186,13 +188,9 @@ putSrcLocDs :: SrcLoc -> DsM a -> DsM a
 putSrcLocDs new_loc expr us old_loc mod_and_grp env warns
   = expr us new_loc mod_and_grp env warns
 
-dsShadowWarn :: DsMatchContext -> DsM ()
-dsShadowWarn cxt us loc mod_and_grp env warns
-  = ((), warns `snocBag` (Shadowed, cxt))
+dsWarn :: WarnMsg -> DsM ()
+dsWarn warn us loc mod_and_grp env warns = ((), warns `snocBag` warn)
 
-dsIncompleteWarn :: DsMatchContext -> DsM ()
-dsIncompleteWarn cxt us loc mod_and_grp env warns
-  = ((), warns `snocBag` (Incomplete, cxt))
 \end{code}
 
 \begin{code}
@@ -224,8 +222,6 @@ lookupEnvDs id us loc mod_and_grp env warns
 %************************************************************************
 
 \begin{code}
-data DsWarnFlavour = Shadowed | Incomplete deriving ()
-
 data DsMatchContext
   = DsMatchContext DsMatchKind [TypecheckedPat] SrcLoc
   | NoMatchContext
@@ -237,45 +233,10 @@ data DsMatchKind
   | LambdaMatch
   | PatBindMatch
   | DoBindMatch
+  | ListCompMatch
+  | LetMatch
   deriving ()
 
-pprDsWarnings :: PprStyle -> DsWarnings -> Doc
-pprDsWarnings sty warns
-  = vcat (map pp_warn (bagToList warns))
-  where
-    pp_warn (flavour, NoMatchContext) = sep [ptext SLIT("Warning: Some match is"), 
-                                              case flavour of
-                                                       Shadowed   -> ptext SLIT("shadowed")
-                                                       Incomplete -> ptext SLIT("possibly incomplete")]
-
-    pp_warn (flavour, DsMatchContext kind pats loc)
-       = hang (hcat [ppr (PprForUser opt_PprUserLength) loc, ptext SLIT(": ")])
-            4 (hang msg
-                    4 (pp_match kind pats))
-       where
-       msg = case flavour of
-               Shadowed   -> ptext SLIT("Warning: Pattern match(es) completely overlapped")     
-               Incomplete -> ptext SLIT("Warning: Possibly incomplete patterns")
-
-    pp_match (FunMatch fun) pats
-      = hsep [ptext SLIT("in the definition of function"), ppr sty fun]
-
-    pp_match CaseMatch pats
-      = hang (ptext SLIT("in a group of case alternatives beginning:"))
-       4 (ppr_pats pats)
-
-    pp_match PatBindMatch pats
-      = hang (ptext SLIT("in a pattern binding:"))
-       4 (ppr_pats pats)
-
-    pp_match LambdaMatch pats
-      = hang (ptext SLIT("in a lambda abstraction:"))
-       4 (ppr_pats pats)
-
-    pp_match DoBindMatch pats
-      = hang (ptext SLIT("in a `do' pattern binding:"))
-       4 (ppr_pats pats)
-
-    ppr_pats pats = pprQuote sty $ \ sty ->
-                   sep [sep (map (ppr sty) pats), ptext SLIT("-> ...")]
+pprDsWarnings :: DsWarnings -> SDoc
+pprDsWarnings warns = vcat (bagToList warns)
 \end{code}