1 files changed, 100 insertions, 0 deletions
diff --git a/compiler/GHC/Data/FastString/Env.hs b/compiler/GHC/Data/FastString/Env.hs
new file mode 100644
index 0000000000..36fab5727c
--- /dev/null
+++ b/compiler/GHC/Data/FastString/Env.hs
@@ -0,0 +1,100 @@
+{-
+%
+% (c) The University of Glasgow 2006
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
+%
+-}
+
+-- | FastStringEnv: FastString environments
+module GHC.Data.FastString.Env (
+        -- * FastString environments (maps)
+        FastStringEnv,
+
+        -- ** Manipulating these environments
+        mkFsEnv,
+        emptyFsEnv, unitFsEnv,
+        extendFsEnv_C, extendFsEnv_Acc, extendFsEnv,
+        extendFsEnvList, extendFsEnvList_C,
+        filterFsEnv,
+        plusFsEnv, plusFsEnv_C, alterFsEnv,
+        lookupFsEnv, lookupFsEnv_NF, delFromFsEnv, delListFromFsEnv,
+        elemFsEnv, mapFsEnv,
+
+        -- * Deterministic FastString environments (maps)
+        DFastStringEnv,
+
+        -- ** Manipulating these environments
+        mkDFsEnv, emptyDFsEnv, dFsEnvElts, lookupDFsEnv
+    ) where
+
+import GHC.Prelude
+
+import GHC.Types.Unique.FM
+import GHC.Types.Unique.DFM
+import GHC.Data.Maybe
+import GHC.Data.FastString
+
+
+-- | A non-deterministic set of FastStrings.
+-- See Note [Deterministic UniqFM] in GHC.Types.Unique.DFM for explanation why it's not
+-- deterministic and why it matters. Use DFastStringEnv if the set eventually
+-- gets converted into a list or folded over in a way where the order
+-- changes the generated code.
+type FastStringEnv a = UniqFM a  -- Domain is FastString
+
+emptyFsEnv         :: FastStringEnv a
+mkFsEnv            :: [(FastString,a)] -> FastStringEnv a
+alterFsEnv         :: (Maybe a-> Maybe a) -> FastStringEnv a -> FastString -> FastStringEnv a
+extendFsEnv_C      :: (a->a->a) -> FastStringEnv a -> FastString -> a -> FastStringEnv a
+extendFsEnv_Acc    :: (a->b->b) -> (a->b) -> FastStringEnv b -> FastString -> a -> FastStringEnv b
+extendFsEnv        :: FastStringEnv a -> FastString -> a -> FastStringEnv a
+plusFsEnv          :: FastStringEnv a -> FastStringEnv a -> FastStringEnv a
+plusFsEnv_C        :: (a->a->a) -> FastStringEnv a -> FastStringEnv a -> FastStringEnv a
+extendFsEnvList    :: FastStringEnv a -> [(FastString,a)] -> FastStringEnv a
+extendFsEnvList_C  :: (a->a->a) -> FastStringEnv a -> [(FastString,a)] -> FastStringEnv a
+delFromFsEnv       :: FastStringEnv a -> FastString -> FastStringEnv a
+delListFromFsEnv   :: FastStringEnv a -> [FastString] -> FastStringEnv a
+elemFsEnv          :: FastString -> FastStringEnv a -> Bool
+unitFsEnv          :: FastString -> a -> FastStringEnv a
+lookupFsEnv        :: FastStringEnv a -> FastString -> Maybe a
+lookupFsEnv_NF     :: FastStringEnv a -> FastString -> a
+filterFsEnv        :: (elt -> Bool) -> FastStringEnv elt -> FastStringEnv elt
+mapFsEnv           :: (elt1 -> elt2) -> FastStringEnv elt1 -> FastStringEnv elt2
+
+emptyFsEnv                = emptyUFM
+unitFsEnv x y             = unitUFM x y
+extendFsEnv x y z         = addToUFM x y z
+extendFsEnvList x l       = addListToUFM x l
+lookupFsEnv x y           = lookupUFM x y
+alterFsEnv                = alterUFM
+mkFsEnv     l             = listToUFM l
+elemFsEnv x y             = elemUFM x y
+plusFsEnv x y             = plusUFM x y
+plusFsEnv_C f x y         = plusUFM_C f x y
+extendFsEnv_C f x y z     = addToUFM_C f x y z
+mapFsEnv f x              = mapUFM f x
+extendFsEnv_Acc x y z a b = addToUFM_Acc x y z a b
+extendFsEnvList_C x y z   = addListToUFM_C x y z
+delFromFsEnv x y          = delFromUFM x y
+delListFromFsEnv x y      = delListFromUFM x y
+filterFsEnv x y           = filterUFM x y
+
+lookupFsEnv_NF env n = expectJust "lookupFsEnv_NF" (lookupFsEnv env n)
+
+-- Deterministic FastStringEnv
+-- See Note [Deterministic UniqFM] in GHC.Types.Unique.DFM for explanation why we need
+-- DFastStringEnv.
+
+type DFastStringEnv a = UniqDFM a  -- Domain is FastString
+
+emptyDFsEnv :: DFastStringEnv a
+emptyDFsEnv = emptyUDFM
+
+dFsEnvElts :: DFastStringEnv a -> [a]
+dFsEnvElts = eltsUDFM
+
+mkDFsEnv :: [(FastString,a)] -> DFastStringEnv a
+mkDFsEnv l = listToUDFM l
+
+lookupDFsEnv :: DFastStringEnv a -> FastString -> Maybe a
+lookupDFsEnv = lookupUDFM