X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcMatches.lhs;h=d11cb9754a9b705811d14fa9777b850ea32e7048;hb=3f1b316d7035c55cd712cd39a9981339bcef2e8c;hp=68e1398972480836cb973866a99dcaefdb141f1b;hpb=ab22f4e6456820c1b5169d75f5975a94e61f54ce;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcMatches.lhs b/compiler/typecheck/TcMatches.lhs
index 68e1398..d11cb97 100644
--- a/compiler/typecheck/TcMatches.lhs
+++ b/compiler/typecheck/TcMatches.lhs
@@ -6,6 +6,13 @@
 TcMatches: Typecheck some @Matches@
 
 \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 TcMatches ( tcMatchesFun, tcGRHSsPat, tcMatchesCase, tcMatchLambda,
 		   matchCtxt, TcMatchCtxt(..), 
 		   tcStmts, tcDoStmts, tcBody,
@@ -48,12 +55,12 @@ is used in error messages.  It checks that all the equations have the
 same number of arguments before using @tcMatches@ to do the work.
 
 \begin{code}
-tcMatchesFun :: Name
+tcMatchesFun :: Name -> Bool
 	     -> MatchGroup Name
 	     -> BoxyRhoType 		-- Expected type of function
 	     -> TcM (HsWrapper, MatchGroup TcId)	-- Returns type of body
 
-tcMatchesFun fun_name matches exp_ty
+tcMatchesFun fun_name inf matches exp_ty
   = do	{  -- Check that they all have the same no of arguments
 	   -- Location is in the monad, set the caller so that 
 	   -- any inter-equation error messages get some vaguely
@@ -76,7 +83,7 @@ tcMatchesFun fun_name matches exp_ty
     doc = ptext SLIT("The equation(s) for") <+> quotes (ppr fun_name)
 	  <+> ptext SLIT("have") <+> speakNOf n_pats (ptext SLIT("argument"))
     n_pats = matchGroupArity matches
-    match_ctxt = MC { mc_what = FunRhs fun_name, mc_body = tcBody }
+    match_ctxt = MC { mc_what = FunRhs fun_name inf, mc_body = tcBody }
 \end{code}
 
 @tcMatchesCase@ doesn't do the argument-count check because the
@@ -99,7 +106,7 @@ tcMatchLambda match res_ty
   where
     n_pats = matchGroupArity match
     doc = sep [ ptext SLIT("The lambda expression")
-		 <+> quotes (pprSetDepth 1 $ pprMatches LambdaExpr match),
+		 <+> quotes (pprSetDepth 1 $ pprMatches (LambdaExpr :: HsMatchContext Name) match),
 			-- The pprSetDepth makes the abstraction print briefly
 		ptext SLIT("has") <+> speakNOf n_pats (ptext SLIT("argument"))]
     match_ctxt = MC { mc_what = LambdaExpr,
@@ -153,7 +160,7 @@ tcMatch ctxt pat_tys rhs_ty match
   = wrapLocM (tc_match ctxt pat_tys rhs_ty) match
   where
     tc_match ctxt pat_tys rhs_ty match@(Match pats maybe_rhs_sig grhss)
-      = addErrCtxt (matchCtxt (mc_what ctxt) match)	$	
+      = add_match_ctxt match $
         do { (pats', grhss') <- tcLamPats pats pat_tys rhs_ty $
     			        tc_grhss ctxt maybe_rhs_sig grhss
 	   ; return (Match pats' Nothing grhss') }
@@ -167,6 +174,13 @@ tcMatch ctxt pat_tys rhs_ty match
 			<+> ppr res_sig)
     	   ; tcGRHSs ctxt grhss (co, rhs_ty) }
 
+	-- For (\x -> e), tcExpr has already said "In the expresssion \x->e"
+	-- so we don't want to add "In the lambda abstraction \x->e"
+    add_match_ctxt match thing_inside
+	= case mc_what ctxt of
+	    LambdaExpr -> thing_inside
+	    m_ctxt     -> addErrCtxt (matchCtxt m_ctxt match) thing_inside
+
 -------------
 tcGRHSs :: TcMatchCtxt -> GRHSs Name -> (Refinement, BoxyRhoType) 
 	-> TcM (GRHSs TcId)
@@ -208,29 +222,31 @@ tcDoStmts :: HsStmtContext Name
 	  -> BoxyRhoType
 	  -> TcM (HsExpr TcId)		-- Returns a HsDo
 tcDoStmts ListComp stmts body res_ty
-  = do	{ elt_ty <- boxySplitListTy res_ty
+  = do	{ (elt_ty, coi) <- boxySplitListTy res_ty
 	; (stmts', body') <- tcStmts ListComp (tcLcStmt listTyCon) stmts 
 				     (emptyRefinement,elt_ty) $
 			     tcBody body
-	; return (HsDo ListComp stmts' body' (mkListTy elt_ty)) }
+	; return $ mkHsWrapCoI coi 
+                     (HsDo ListComp stmts' body' (mkListTy elt_ty)) }
 
 tcDoStmts PArrComp stmts body res_ty
-  = do	{ [elt_ty] <- boxySplitTyConApp parrTyCon res_ty
+  = do	{ (elt_ty, coi) <- boxySplitPArrTy res_ty
 	; (stmts', body') <- tcStmts PArrComp (tcLcStmt parrTyCon) stmts 
 				     (emptyRefinement, elt_ty) $
 			     tcBody body
-	; return (HsDo PArrComp stmts' body' (mkPArrTy elt_ty)) }
+	; return $ mkHsWrapCoI coi 
+                     (HsDo PArrComp stmts' body' (mkPArrTy elt_ty)) }
 
 tcDoStmts DoExpr stmts body res_ty
-  = do	{ (m_ty, elt_ty) <- boxySplitAppTy res_ty
+  = do	{ ((m_ty, elt_ty), coi) <- boxySplitAppTy res_ty
 	; let res_ty' = mkAppTy m_ty elt_ty	-- The boxySplit consumes res_ty
 	; (stmts', body') <- tcStmts DoExpr (tcDoStmt m_ty) stmts 
 				     (emptyRefinement, res_ty') $
 			     tcBody body
-	; return (HsDo DoExpr stmts' body' res_ty') }
+	; return $ mkHsWrapCoI coi (HsDo DoExpr stmts' body' res_ty') }
 
 tcDoStmts ctxt@(MDoExpr _) stmts body res_ty
-  = do	{ (m_ty, elt_ty) <- boxySplitAppTy res_ty
+  = do	{ ((m_ty, elt_ty), coi) <- boxySplitAppTy res_ty
  	; let res_ty' = mkAppTy m_ty elt_ty	-- The boxySplit consumes res_ty
 	      tc_rhs rhs = withBox liftedTypeKind $ \ pat_ty ->
 			   tcMonoExpr rhs (mkAppTy m_ty pat_ty)
@@ -241,7 +257,9 @@ tcDoStmts ctxt@(MDoExpr _) stmts body res_ty
 
 	; let names = [mfixName, bindMName, thenMName, returnMName, failMName]
 	; insts <- mapM (newMethodFromName DoOrigin m_ty) names
-	; return (HsDo (MDoExpr (names `zip` insts)) stmts' body' res_ty') }
+	; return $ 
+            mkHsWrapCoI coi 
+              (HsDo (MDoExpr (names `zip` insts)) stmts' body' res_ty') }
 
 tcDoStmts ctxt stmts body res_ty = pprPanic "tcDoStmts" (pprStmtContext ctxt)