[project @ 2004-09-30 10:35:15 by simonpj]

[ghc-hetmet.git] / ghc / compiler / deSugar / Desugar.lhs

diff --git a/ghc/compiler/deSugar/Desugar.lhs b/ghc/compiler/deSugar/Desugar.lhs
index 84b7216..02c475f 100644 (file)
--- a/ghc/compiler/deSugar/Desugar.lhs
+++ b/ghc/compiler/deSugar/Desugar.lhs
@@ -10,8 +10,7 @@ module Desugar ( deSugar, deSugarExpr ) where
 
 import CmdLineOpts     ( DynFlag(..), dopt, opt_SccProfilingOn )
 import HscTypes                ( ModGuts(..), ModGuts, HscEnv(..), GhciMode(..),
-                         Dependencies(..), TypeEnv, 
-                         unQualInScope, availsToNameSet )
+                         Dependencies(..), TypeEnv, unQualInScope )
 import HsSyn           ( RuleDecl(..), RuleBndr(..), HsExpr(..), LHsExpr,
                          HsBindGroup(..), LRuleDecl, HsBind(..) )
 import TcRnTypes       ( TcGblEnv(..), ImportAvails(..) )
@@ -20,14 +19,14 @@ import Id           ( Id, setIdLocalExported, idName )
 import Name            ( Name, isExternalName )
 import CoreSyn
 import PprCore         ( pprIdRules, pprCoreExpr )
-import Subst           ( substExpr, mkSubst, mkInScopeSet )
+import Subst           ( SubstResult(..), substExpr, mkSubst, extendIdSubstList )
 import DsMonad
 import DsExpr          ( dsLExpr )
 import DsBinds         ( dsHsBinds, AutoScc(..) )
 import DsForeign       ( dsForeigns )
 import DsExpr          ()      -- Forces DsExpr to be compiled; DsBinds only
                                -- depends on DsExpr.hi-boot.
-import Module          ( Module, moduleEnvElts, emptyModuleEnv )
+import Module          ( Module, moduleEnvElts )
 import Id              ( Id )
 import RdrName         ( GlobalRdrEnv )
 import NameSet
@@ -277,12 +276,10 @@ ds_lhs all_vars lhs
        -- Substitute the dict bindings eagerly,
        -- and take the body apart into a (f args) form
     let
-       subst_env = mkSubstEnv [id                   | (id,rhs) <- dict_binds']
-                              [ContEx subst_env rhs | (id,rhs) <- dict_binds']
+       subst = extendIdSubstList (mkSubst all_vars) pairs
+       pairs = [(id, ContEx subst rhs) | (id,rhs) <- dict_binds']
                        -- Note recursion here... substitution won't terminate
                        -- if there is genuine recursion... which there isn't
-
-       subst = mkSubst all_vars subst_env
        body'' = substExpr subst body'
     in