From 6d77d64938e687bb5788ee3662e2ed2856bc7a4f Mon Sep 17 00:00:00 2001
From: simonpj <unknown>
Date: Wed, 7 Nov 2001 15:11:33 +0000
Subject: [PATCH] [project @ 2001-11-07 15:11:33 by simonpj] Wibble in zonking
 of rules; fixes Manuels problem

---
 ghc/compiler/typecheck/TcHsSyn.lhs |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/ghc/compiler/typecheck/TcHsSyn.lhs b/ghc/compiler/typecheck/TcHsSyn.lhs
index dfe9f95..d540305 100644
--- a/ghc/compiler/typecheck/TcHsSyn.lhs
+++ b/ghc/compiler/typecheck/TcHsSyn.lhs
@@ -50,6 +50,7 @@ import Type	  ( Type )
 import TcMType	  ( zonkTcTypeToType, zonkTcTyVarToTyVar, zonkTcType, zonkTcSigTyVars )
 import TysWiredIn ( mkListTy, mkTupleTy, unitTy )
 import CoreSyn    ( Expr )
+import Var	  ( isId )
 import BasicTypes ( RecFlag(..), Boxity(..) )
 import Bag
 import Outputable
@@ -717,12 +718,18 @@ zonkRules :: [TcRuleDecl] -> NF_TcM [TypecheckedRuleDecl]
 zonkRules rs = mapNF_Tc zonkRule rs
 
 zonkRule (HsRule name act vars lhs rhs loc)
-  = mapNF_Tc zonkIdBndr [v | RuleBndr v <- vars]	`thenNF_Tc` \ new_bndrs ->
-    tcExtendGlobalValEnv new_bndrs			$
+  = mapNF_Tc zonk_bndr vars				`thenNF_Tc` \ new_bndrs ->
+    tcExtendGlobalValEnv (filter isId new_bndrs)	$
+	-- Type variables don't need an envt
+	-- They are bound through the mutable mechanism
     zonkExpr lhs					`thenNF_Tc` \ new_lhs ->
     zonkExpr rhs					`thenNF_Tc` \ new_rhs ->
     returnNF_Tc (HsRule name act (map RuleBndr new_bndrs) new_lhs new_rhs loc)
 	-- I hate this map RuleBndr stuff
+  where
+   zonk_bndr (RuleBndr v) 
+	| isId v    = zonkIdBndr v
+	| otherwise = zonkTcTyVarToTyVar v
 
 zonkRule (IfaceRuleOut fun rule)
   = zonkIdOcc fun	`thenNF_Tc` \ fun' ->
-- 
1.7.10.4