[project @ 2000-11-07 15:21:38 by simonmar]

[ghc-hetmet.git] / ghc / compiler / typecheck / TcUnify.lhs

diff --git a/ghc/compiler/typecheck/TcUnify.lhs b/ghc/compiler/typecheck/TcUnify.lhs
index 0944e63..f9ebae4 100644 (file)
--- a/ghc/compiler/typecheck/TcUnify.lhs
+++ b/ghc/compiler/typecheck/TcUnify.lhs
@@ -21,7 +21,7 @@ import Type   ( unboxedTypeKind, boxedTypeKind, openTypeKind,
                  typeCon, openKindCon, hasMoreBoxityInfo, 
                  tyVarsOfType, typeKind,
                  mkFunTy, splitFunTy_maybe, splitTyConApp_maybe,
-                  isNotUsgTy, splitAppTy_maybe, mkTyConApp, 
+                  splitAppTy_maybe, mkTyConApp, 
                  tidyOpenType, tidyOpenTypes, tidyTyVar
                )
 import TyCon   ( TyCon, isTupleTyCon, tupleTyConBoxity, tyConArity )
@@ -148,10 +148,14 @@ uTys :: TcTauType -> TcTauType    -- Error reporting ty1 and real ty1
      -> TcM ()
 
        -- Always expand synonyms (see notes at end)
-        -- (this also throws away FTVs and usage annots)
+        -- (this also throws away FTVs)
 uTys ps_ty1 (NoteTy _ ty1) ps_ty2 ty2 = uTys ps_ty1 ty1 ps_ty2 ty2
 uTys ps_ty1 ty1 ps_ty2 (NoteTy _ ty2) = uTys ps_ty1 ty1 ps_ty2 ty2
 
+       -- Ignore usage annotations inside typechecker
+uTys ps_ty1 (UsageTy _ ty1) ps_ty2 ty2 = uTys ps_ty1 ty1 ps_ty2 ty2
+uTys ps_ty1 ty1 ps_ty2 (UsageTy _ ty2) = uTys ps_ty1 ty1 ps_ty2 ty2
+
        -- Variables; go for uVar
 uTys ps_ty1 (TyVarTy tyvar1) ps_ty2 ty2 = uVar False tyvar1 ps_ty2 ty2
 uTys ps_ty1 ty1 ps_ty2 (TyVarTy tyvar2) = uVar True  tyvar2 ps_ty1 ty1
@@ -279,7 +283,7 @@ uVar swapped tv1 ps_ty2 ty2
                 | otherwise -> uTys ty1 ty1 ps_ty2 ty2 -- Same order
        other       -> uUnboundVar swapped tv1 maybe_ty1 ps_ty2 ty2
 
-       -- Expand synonyms; ignore FTVs; ignore usage annots
+       -- Expand synonyms; ignore FTVs
 uUnboundVar swapped tv1 maybe_ty1 ps_ty2 (NoteTy _ ty2)
   = uUnboundVar swapped tv1 maybe_ty1 ps_ty2 ty2
 
@@ -306,8 +310,7 @@ uUnboundVar swapped tv1 maybe_ty1 ps_ty2 ty2@(TyVarTy tv2)
                |  otherwise
 
                -> WARN( not (k2 `hasMoreBoxityInfo` k1), (ppr tv2 <+> ppr k2) $$ (ppr tv1 <+> ppr k1) )
-                   (ASSERT( isNotUsgTy ps_ty2 )
-                   tcPutTyVar tv1 ps_ty2               `thenNF_Tc_`
+                   (tcPutTyVar tv1 ps_ty2              `thenNF_Tc_`
                    returnTc ())
   where
     k1 = tyVarKind tv1