X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnTypes.lhs;h=227cce53569dd90f8cf6f704e163c0e18682bf74;hb=8c7c30b1221025c0cffb1f14d014078b6e3055fc;hp=4b6f799cf556139cb7c91f54cca66f65fae8ef18;hpb=98688c6e8fd33f31c51218cf93cbf03fe3a5e73d;p=ghc-hetmet.git

diff --git a/ghc/compiler/rename/RnTypes.lhs b/ghc/compiler/rename/RnTypes.lhs
index 4b6f799..227cce5 100644
--- a/ghc/compiler/rename/RnTypes.lhs
+++ b/ghc/compiler/rename/RnTypes.lhs
@@ -75,7 +75,7 @@ want a gratuitous knot.
 \begin{code}
 rnHsType :: SDoc -> RdrNameHsType -> RnM RenamedHsType
 
-rnHsType doc (HsForAllTy Nothing ctxt ty)
+rnHsType doc (HsForAllTy Implicit _ ctxt ty)
 	-- Implicit quantifiction in source code (no kinds on tyvars)
 	-- Given the signature  C => T  we universally quantify 
 	-- over FV(T) \ {in-scope-tyvars} 
@@ -89,9 +89,9 @@ rnHsType doc (HsForAllTy Nothing ctxt ty)
 	--	class C a where { op :: a -> a }
 	forall_tyvars = filter (not . (`elemLocalRdrEnv` name_env)) mentioned
     in
-    rnForAll doc (map UserTyVar forall_tyvars) ctxt ty
+    rnForAll doc Implicit (map UserTyVar forall_tyvars) ctxt ty
 
-rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
+rnHsType doc (HsForAllTy Explicit forall_tyvars ctxt tau)
 	-- Explicit quantification.
 	-- Check that the forall'd tyvars are actually 
 	-- mentioned in the type, and produce a warning if not
@@ -103,7 +103,7 @@ rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
 	warn_guys = filter (`notElem` mentioned) forall_tyvar_names
     in
     mappM_ (forAllWarn doc tau) warn_guys	`thenM_`
-    rnForAll doc forall_tyvars ctxt tau
+    rnForAll doc Explicit forall_tyvars ctxt tau
 
 rnHsType doc (HsTyVar tyvar)
   = lookupOccRn tyvar 		`thenM` \ tyvar' ->
@@ -167,11 +167,22 @@ rnHsTypes doc tys = mappM (rnHsType doc) tys
 
 
 \begin{code}
-rnForAll doc forall_tyvars ctxt ty
+rnForAll doc exp [] [] ty = rnHsType doc ty
+	-- One reason for this case is that a type like Int#
+	-- starts of as (HsForAllTy Nothing [] Int), in case
+	-- there is some quantification.  Now that we have quantified
+	-- and discovered there are no type variables, it's nicer to turn
+	-- it into plain Int.  If it were Int# instead of Int, we'd actually
+	-- get an error, because the body of a genuine for-all is
+	-- of kind *.
+
+rnForAll doc exp forall_tyvars ctxt ty
   = bindTyVarsRn doc forall_tyvars	$ \ new_tyvars ->
     rnContext doc ctxt			`thenM` \ new_ctxt ->
     rnHsType doc ty			`thenM` \ new_ty ->
-    returnM (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty)
+    returnM (HsForAllTy exp new_tyvars new_ctxt new_ty)
+	-- Retain the same implicit/explicit flag as before
+	-- so that we can later print it correctly
 \end{code}