From 55c1f08cf6b8812f60b0c45882442c146bb9e92a Mon Sep 17 00:00:00 2001 From: "simonpj@microsoft.com" Date: Fri, 23 Oct 2009 16:17:35 +0000 Subject: [PATCH] Add restrictVarEnv :: VarEnv a -> VarSet -> VarEnv a I needed it, and then didn't need it, so it's not currently called, but its generally useful kind of thing. --- compiler/basicTypes/VarEnv.lhs | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/compiler/basicTypes/VarEnv.lhs b/compiler/basicTypes/VarEnv.lhs index 7e28d1a..2699748 100644 --- a/compiler/basicTypes/VarEnv.lhs +++ b/compiler/basicTypes/VarEnv.lhs @@ -19,7 +19,7 @@ module VarEnv ( modifyVarEnv, modifyVarEnv_Directly, isEmptyVarEnv, foldVarEnv, elemVarEnvByKey, lookupVarEnv_Directly, - filterVarEnv_Directly, + filterVarEnv_Directly, restrictVarEnv, -- * The InScopeSet type InScopeSet, @@ -321,6 +321,7 @@ extendVarEnvList :: VarEnv a -> [(Var, a)] -> VarEnv a lookupVarEnv_Directly :: VarEnv a -> Unique -> Maybe a filterVarEnv_Directly :: (Unique -> a -> Bool) -> VarEnv a -> VarEnv a +restrictVarEnv :: VarEnv a -> VarSet -> VarEnv a delVarEnvList :: VarEnv a -> [Var] -> VarEnv a delVarEnv :: VarEnv a -> Var -> VarEnv a plusVarEnv_C :: (a -> a -> a) -> VarEnv a -> VarEnv a -> VarEnv a @@ -361,6 +362,10 @@ foldVarEnv = foldUFM lookupVarEnv_Directly = lookupUFM_Directly filterVarEnv_Directly = filterUFM_Directly +restrictVarEnv env vs = filterVarEnv_Directly keep env + where + keep u _ = u `elemVarSetByKey` vs + zipVarEnv tyvars tys = mkVarEnv (zipEqual "zipVarEnv" tyvars tys) lookupVarEnv_NF env id = case lookupVarEnv env id of Just xx -> xx -- 1.7.10.4