X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FhsSyn%2FHsPat.lhs;h=42da26554a748a383f36cf2629b0e8b36cdadbb3;hb=74b27e20425336403d80e942ee3faf00f8c36ef8;hp=65cc304999eb1e23a09d65ee294e8c59233921d3;hpb=ab22f4e6456820c1b5169d75f5975a94e61f54ce;p=ghc-hetmet.git

diff --git a/compiler/hsSyn/HsPat.lhs b/compiler/hsSyn/HsPat.lhs
index 65cc304..42da265 100644
--- a/compiler/hsSyn/HsPat.lhs
+++ b/compiler/hsSyn/HsPat.lhs
@@ -50,6 +50,9 @@ type LPat id = Located (Pat id)
 data Pat id
   =	------------ Simple patterns ---------------
     WildPat	PostTcType		-- Wild card
+	-- The sole reason for a type on a WildPat is to
+	-- support hsPatType :: Pat Id -> Type
+
   | VarPat	id			-- Variable
   | VarPatOut	id (DictBinds id)	-- Used only for overloaded Ids; the 
 					-- bindings give its overloaded instances
@@ -122,16 +125,11 @@ data Pat id
   | SigPatOut	    (LPat id)		-- Pattern with a type signature
 		    Type
 
-	------------ Dictionary patterns (translation only) ---------------
-  | DictPat	    -- Used when destructing Dictionaries with an explicit case
-		    [id]		-- Superclass dicts
-		    [id]		-- Methods
-
 	------------ Pattern coercions (translation only) ---------------
   | CoPat 	HsWrapper		-- If co::t1 -> t2, p::t2, 
 					-- then (CoPat co p) :: t1
 		(Pat id)		-- Why not LPat?  Ans: existing locn will do
-	    	Type
+	    	Type			-- Type of whole pattern, t1
 	-- During desugaring a (CoPat co pat) turns into a cast with 'co' on 
 	-- the scrutinee, followed by a match on 'pat'
 \end{code}
@@ -208,9 +206,6 @@ pprPat (TypePat ty)	      = ptext SLIT("{|") <> ppr ty <> ptext SLIT("|}")
 pprPat (CoPat co pat _)	      = parens (pprHsWrapper (ppr pat) co)
 pprPat (SigPatIn pat ty)      = ppr pat <+> dcolon <+> ppr ty
 pprPat (SigPatOut pat ty)     = ppr pat <+> dcolon <+> ppr ty
-pprPat (DictPat ds ms)	      = parens (sep [ptext SLIT("{-dict-}"),
-					     brackets (interpp'SP ds),
-					     brackets (interpp'SP ms)])
 
 pprUserCon c (InfixCon p1 p2) = ppr p1 <+> ppr c <+> ppr p2
 pprUserCon c details          = ppr c <+> pprConArgs details
@@ -219,8 +214,8 @@ pprConArgs (PrefixCon pats) = interppSP pats
 pprConArgs (InfixCon p1 p2) = interppSP [p1,p2]
 pprConArgs (RecCon rpats)   = braces (hsep (punctuate comma (map (pp_rpat) rpats)))
 			    where
-			      pp_rpat (HsRecField v p d) = 
-                                hsep [ppr d, ppr v, char '=', ppr p]
+			      pp_rpat (HsRecField v p _d) = 
+                                hsep [ppr v, char '=', ppr p]
 
 -- add parallel array brackets around a document
 --
@@ -302,7 +297,6 @@ isConPat (ConPatOut {})  = True
 isConPat (ListPat {})	 = True
 isConPat (PArrPat {})	 = True
 isConPat (TuplePat {})	 = True
-isConPat (DictPat ds ms) = (length ds + length ms) > 1
 isConPat other		 = False
 
 isSigPat (SigPatIn _ _)  = True
@@ -356,6 +350,5 @@ isIrrefutableHsPat pat
     go1 (NPlusKPat _ _ _ _) = False
 
     go1 (TypePat _)   = panic "isIrrefutableHsPat: type pattern"
-    go1 (DictPat _ _) = panic "isIrrefutableHsPat: type pattern"
 \end{code}