X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcArrows.lhs;h=231901c068484494c8249f13e9bc285708765258;hb=d54de1579e43421350f6282af8977706606973b9;hp=9fede384a7d2108d15ac65a1a9f9f53c4c8e1821;hpb=d436c70d43fb905c63220040168295e473f4b90a;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcArrows.lhs b/compiler/typecheck/TcArrows.lhs
index 9fede38..231901c 100644
--- a/compiler/typecheck/TcArrows.lhs
+++ b/compiler/typecheck/TcArrows.lhs
@@ -294,14 +294,13 @@ tc_cmd env cmd@(HsArrForm expr fixity cmd_args) (cmd_stk, res_ty)
 
     unscramble :: TcType -> (TcType, [TcType])
     -- unscramble ((w,s1) .. sn)	=  (w, [s1..sn])
-    unscramble ty
+    unscramble ty = unscramble' ty []
+
+    unscramble' ty ss
        = case tcSplitTyConApp_maybe ty of
 	    Just (tc, [t,s]) | tc == pairTyCon 
-	       ->  let 
-		      (w,ss) = unscramble t  
-		   in (w, s:ss)
-				    
-	    _ -> (ty, [])
+	       ->  unscramble' t (s:ss)
+	    _ -> (ty, ss)
 
 -----------------------------------------------------------------
 --		Base case for illegal commands