X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Frename%2FRnExpr.lhs;h=1b7eef0253534341c78f571393c7eea67c5fb76f;hp=6d425d0822ee25f06d7dbb4030138c2f3b988715;hb=cf5905ea24904cf73a041fd7535e8723a668cb9a;hpb=024aa13a0a6bfd2d68f4c551824357b87e732f5b

diff --git a/compiler/rename/RnExpr.lhs b/compiler/rename/RnExpr.lhs
index 6d425d0..1b7eef0 100644
--- a/compiler/rename/RnExpr.lhs
+++ b/compiler/rename/RnExpr.lhs
@@ -25,7 +25,7 @@ import RnBinds   ( rnLocalBindsAndThen, rnLocalValBindsLHS, rnLocalValBindsRHS,
                    rnMatchGroup, makeMiniFixityEnv) 
 import HsSyn
 import TcRnMonad
-import TcEnv		( thRnBrack )
+import TcEnv		( thRnBrack, getHetMetLevel )
 import RnEnv
 import RnTypes		( rnHsTypeFVs, rnSplice, checkTH,
 			  mkOpFormRn, mkOpAppRn, mkNegAppRn, checkSectionPrec)
@@ -34,6 +34,7 @@ import DynFlags
 import BasicTypes	( FixityDirection(..) )
 import PrelNames
 
+import Var              ( TyVar, varName )
 import Name
 import NameSet
 import RdrName
@@ -84,6 +85,13 @@ rnExprs ls = rnExprs' ls emptyUniqSet
 Variables. We look up the variable and return the resulting name. 
 
 \begin{code}
+
+-- during the renamer phase we only care about the length of the
+-- current HetMet level; the actual tyvars don't
+-- matter, so we use bottoms for them
+dummyTyVar :: TyVar
+dummyTyVar = error "tried to force RnExpr.dummyTyVar"
+
 rnLExpr :: LHsExpr RdrName -> RnM (LHsExpr Name, FreeVars)
 rnLExpr = wrapLocFstM rnExpr
 
@@ -157,6 +165,21 @@ rnExpr (NegApp e _)
     mkNegAppRn e' neg_name	`thenM` \ final_e ->
     return (final_e, fv_e `plusFV` fv_neg)
 
+rnExpr (HsHetMetBrak c e)
+  = do { (e', fv_e) <- updLclEnv (\x -> x { tcl_hetMetLevel = dummyTyVar:(tcl_hetMetLevel x) }) $ rnLExpr e
+       ; return (HsHetMetBrak c e', fv_e)
+       }
+rnExpr (HsHetMetEsc c t e)
+  = do { (e', fv_e) <- updLclEnv (\x -> x { tcl_hetMetLevel = tail (tcl_hetMetLevel x) }) $ rnLExpr e
+       ; return (HsHetMetEsc c t e', fv_e)
+       }
+rnExpr (HsHetMetCSP c e)
+  = do { (e', fv_e) <- updLclEnv (\x -> x { tcl_hetMetLevel = tail (tcl_hetMetLevel x) }) $ rnLExpr e
+       ; return (HsHetMetCSP c e', fv_e)
+       }
+
+    
+
 ------------------------------------------
 -- Template Haskell extensions
 -- Don't ifdef-GHCI them because we want to fail gracefully
@@ -268,13 +291,10 @@ rnExpr (ExprWithTySig expr pty)
 
 rnExpr (HsIf _ p b1 b2)
   = do { (p', fvP) <- rnLExpr p
-    ; (b1', fvB1) <- rnLExpr b1
-    ; (b2', fvB2) <- rnLExpr b2
-    ; rebind <- xoptM Opt_RebindableSyntax
-    ; if not rebind
-       then return (HsIf Nothing p' b1' b2', plusFVs [fvP, fvB1, fvB2])
-       else do { c <- liftM HsVar (lookupOccRn (mkVarUnqual (fsLit "ifThenElse")))
-               ; return (HsIf (Just c) p' b1' b2', plusFVs [fvP, fvB1, fvB2]) }}
+       ; (b1', fvB1) <- rnLExpr b1
+       ; (b2', fvB2) <- rnLExpr b2
+       ; (mb_ite, fvITE) <- lookupIfThenElse
+       ; return (HsIf mb_ite p' b1' b2', plusFVs [fvITE, fvP, fvB1, fvB2]) }
 
 rnExpr (HsType a)
   = rnHsTypeFVs doc a	`thenM` \ (t, fvT) -> 
@@ -874,13 +894,15 @@ rnRecStmtsAndThen s cont
 
 	  --    ...bring them and their fixities into scope
 	; let bound_names = collectLStmtsBinders (map fst new_lhs_and_fv)
+	      -- Fake uses of variables introduced implicitly (warning suppression, see #4404)
+	      implicit_uses = lStmtsImplicits (map fst new_lhs_and_fv)
 	; bindLocalNamesFV bound_names $
           addLocalFixities fix_env bound_names $ do
 
 	  -- (C) do the right-hand-sides and thing-inside
 	{ segs <- rn_rec_stmts bound_names new_lhs_and_fv
 	; (res, fvs) <- cont segs 
-	; warnUnusedLocalBinds bound_names fvs
+	; warnUnusedLocalBinds bound_names (fvs `unionNameSets` implicit_uses)
 	; return (res, fvs) }}
 
 -- get all the fixity decls in any Let stmt