X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FUnify.lhs;h=77742f4db54fd893b98e9abd06377146b95aabb7;hb=e7498a3ee1d0484d02a9e86633cc179c76ebf36e;hp=ad979b77349cd0f4c68326c7aeffbf99cf75fde5;hpb=f01a8e8c9c53bfb5ab3393ed3457ebf25390efa1;p=ghc-hetmet.git

diff --git a/ghc/compiler/typecheck/Unify.lhs b/ghc/compiler/typecheck/Unify.lhs
index ad979b7..77742f4 100644
--- a/ghc/compiler/typecheck/Unify.lhs
+++ b/ghc/compiler/typecheck/Unify.lhs
@@ -11,10 +11,10 @@ updatable substitution).
 
 module Unify ( unifyTauTy, unifyTauTyList, unifyTauTyLists, unifyFunTy ) where
 
-import Ubiq
+IMP_Ubiq()
 
 -- friends: 
-import TcMonad
+import TcMonad	hiding ( rnMtoTcM )
 import Type	( GenType(..), typeKind, mkFunTy, getFunTy_maybe )
 import TyCon	( TyCon, mkFunTyCon )
 import TyVar	( GenTyVar(..), TyVar(..), tyVarKind )
@@ -229,15 +229,24 @@ uUnboundVar tv1@(TyVar uniq1 kind1 name1 box1)
     case (maybe_ty1, maybe_ty2) of
 	(_, BoundTo ty2') -> uUnboundVar tv1 maybe_ty1 ty2' ty2'
 
-	(DontBind,DontBind) 
-		     -> failTc (unifyDontBindErr tv1 ps_ty2)
-
 	(UnBound, _) |  kind2 `hasMoreBoxityInfo` kind1
 		     -> tcWriteTyVar tv1 ty2		`thenNF_Tc_` returnTc ()
 	
 	(_, UnBound) |  kind1 `hasMoreBoxityInfo` kind2
 		     -> tcWriteTyVar tv2 (TyVarTy tv1)	`thenNF_Tc_` returnTc ()
 
+-- TEMPORARY FIX
+--	(DontBind,DontBind) 
+--		     -> failTc (unifyDontBindErr tv1 ps_ty2)
+
+-- TEMPORARILY allow two type-sig variables to be bound together.
+-- See notes in tcCheckSigVars
+	(DontBind,DontBind) |  kind2 `hasMoreBoxityInfo` kind1
+		            -> tcWriteTyVar tv1 ty2		`thenNF_Tc_` returnTc ()
+	
+			    |  kind1 `hasMoreBoxityInfo` kind2
+			    -> tcWriteTyVar tv2 (TyVarTy tv1)	`thenNF_Tc_` returnTc ()
+
 	other	     -> failTc (unifyKindErr tv1 ps_ty2)
 
 	-- Second one isn't a type variable
@@ -330,9 +339,9 @@ expectedFunErr ty sty
 
 unifyKindErr tyvar ty sty
   = ppHang (ppStr "Compiler bug: kind mis-match between")
-	 4 (ppSep [ppr sty tyvar, ppLparen, ppr sty (tyVarKind tyvar), ppRparen,
+	 4 (ppSep [ppCat [ppr sty tyvar, ppStr "::", ppr sty (tyVarKind tyvar)],
 		   ppStr "and", 
-		   ppr sty ty, ppLparen, ppr sty (typeKind ty), ppRparen])
+		   ppCat [ppr sty ty, ppStr "::", ppr sty (typeKind ty)]])
 
 unifyDontBindErr tyvar ty sty
   = ppHang (ppStr "Couldn't match the *signature/existential* type variable")