X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcRules.lhs;h=a95251d1b40627c24aa6660f3068ecadae519ac6;hb=f04dead93a15af1cb818172f207b8a81d2c81298;hp=0a2babe3f81f448b5053be15a0b7cf247975495b;hpb=f4510d27c5883fe7e8570f4dd49d45a8b0122f2c;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcRules.lhs b/compiler/typecheck/TcRules.lhs
index 0a2babe..a95251d 100644
--- a/compiler/typecheck/TcRules.lhs
+++ b/compiler/typecheck/TcRules.lhs
@@ -8,8 +8,6 @@ TcRules: Typechecking transformation rules
 \begin{code}
 module TcRules ( tcRules ) where
 
-#include "HsVersions.h"
-
 import HsSyn
 import TcRnMonad
 import TcSimplify
@@ -23,29 +21,29 @@ import Id
 import Name
 import SrcLoc
 import Outputable
+import FastString
 \end{code}
 
 \begin{code}
 tcRules :: [LRuleDecl Name] -> TcM [LRuleDecl TcId]
-tcRules decls = mappM (wrapLocM tcRule) decls
+tcRules decls = mapM (wrapLocM tcRule) decls
 
 tcRule :: RuleDecl Name -> TcM (RuleDecl TcId)
 tcRule (HsRule name act vars lhs fv_lhs rhs fv_rhs)
-  = addErrCtxt (ruleCtxt name)			$
-    traceTc (ptext SLIT("---- Rule ------")
-		 <+> ppr name)			`thenM_` 
-    newFlexiTyVarTy openTypeKind		`thenM` \ rule_ty ->
+  = addErrCtxt (ruleCtxt name)			$ do
+    traceTc (ptext (sLit "---- Rule ------") <+> ppr name)
+    rule_ty <- newFlexiTyVarTy openTypeKind
 
 	-- Deal with the tyvars mentioned in signatures
-    tcRuleBndrs vars (\ ids ->
+    (ids, lhs', rhs', lhs_lie, rhs_lie) <-
+      tcRuleBndrs vars $ \ ids -> do
 		-- Now LHS and RHS
-	getLIE (tcMonoExpr lhs rule_ty)	`thenM` \ (lhs', lhs_lie) ->
-	getLIE (tcMonoExpr rhs rule_ty)	`thenM` \ (rhs', rhs_lie) ->
-	returnM (ids, lhs', rhs', lhs_lie, rhs_lie)
-    )				`thenM` \ (ids, lhs', rhs', lhs_lie, rhs_lie) ->
+        (lhs', lhs_lie) <- getLIE (tcMonoExpr lhs rule_ty)
+        (rhs', rhs_lie) <- getLIE (tcMonoExpr rhs rule_ty)
+        return (ids, lhs', rhs', lhs_lie, rhs_lie)
 
 		-- Check that LHS has no overloading at all
-    tcSimplifyRuleLhs lhs_lie	`thenM` \ (lhs_dicts, lhs_binds) ->
+    (lhs_dicts, lhs_binds) <- tcSimplifyRuleLhs lhs_lie
 
 	-- Gather the template variables and tyvars
     let
@@ -72,25 +70,23 @@ tcRule (HsRule name act vars lhs fv_lhs rhs fv_rhs)
 	-- during zonking (see TcHsSyn.zonkRule)
 	--
 	forall_tvs = tyVarsOfTypes (rule_ty : map idType tpl_ids)
-    in
+
 	-- RHS can be a bit more lenient.  In particular,
 	-- we let constant dictionaries etc float outwards
 	--
 	-- NB: tcSimplifyInferCheck zonks the forall_tvs, and 
 	--     knocks out any that are constrained by the environment
-    getInstLoc (SigOrigin (RuleSkol name))	`thenM` \ loc -> 
-    tcSimplifyInferCheck loc
-			 forall_tvs
-			 lhs_dicts rhs_lie	`thenM` \ (forall_tvs1, rhs_binds) ->
-    mappM zonkQuantifiedTyVar forall_tvs1 	`thenM` \ forall_tvs2 ->
-	-- This zonk is exactly the same as the one in TcBinds.tcBindWithSigs
-
-    returnM (HsRule name act
-		    (map (RuleBndr . noLoc) (forall_tvs2 ++ tpl_ids))	-- yuk
+    loc <- getInstLoc (SigOrigin (RuleSkol name))
+    (forall_tvs1, rhs_binds) <- tcSimplifyInferCheck loc
+                                        forall_tvs
+                                        lhs_dicts rhs_lie
+
+    return (HsRule name act
+		    (map (RuleBndr . noLoc) (forall_tvs1 ++ tpl_ids))	-- yuk
 		    (mkHsDictLet lhs_binds lhs') fv_lhs
 		    (mkHsDictLet rhs_binds rhs') fv_rhs)
 
-
+tcRuleBndrs :: [RuleBndr Name] -> ([Id] -> TcM a) -> TcM a
 tcRuleBndrs [] thing_inside = thing_inside []
 tcRuleBndrs (RuleBndr var : vars) thing_inside
   = do 	{ ty <- newFlexiTyVarTy openTypeKind
@@ -110,7 +106,8 @@ tcRuleBndrs (RuleBndrSig var rn_ty : vars) thing_inside
 	  tcExtendIdEnv [id] $
 	  tcRuleBndrs vars (\ids -> thing_inside (id:ids)) }
 
-ruleCtxt name = ptext SLIT("When checking the transformation rule") <+> 
+ruleCtxt :: FastString -> SDoc
+ruleCtxt name = ptext (sLit "When checking the transformation rule") <+> 
 		doubleQuotes (ftext name)
 \end{code}