{-
(c) The University of Glasgow 2006
(c) The GRASP/AQUA Project, Glasgow University, 1992-1998
-}

module GHC.Types.Var.Env (
        -- * Var, Id and TyVar environments (maps)
        VarEnv, IdEnv, TyVarEnv, CoVarEnv, TyCoVarEnv,

        -- ** Manipulating these environments
        emptyVarEnv, unitVarEnv, mkVarEnv, mkVarEnv_Directly,
        elemVarEnv, disjointVarEnv, anyVarEnv,
        extendVarEnv, extendVarEnv_C, extendVarEnv_Acc,
        extendVarEnvList,
        plusVarEnv, plusVarEnv_C, plusVarEnv_CD, plusMaybeVarEnv_C,
        plusVarEnvList, alterVarEnv,
        delVarEnvList, delVarEnv,
        minusVarEnv,
        lookupVarEnv, lookupVarEnv_NF, lookupWithDefaultVarEnv,
        lookupVarEnv_Directly,
        mapVarEnv, zipVarEnv,
        modifyVarEnv, modifyVarEnv_Directly,
        isEmptyVarEnv,
        elemVarEnvByKey,
        filterVarEnv, restrictVarEnv,
        partitionVarEnv, varEnvDomain,
        nonDetStrictFoldVarEnv_Directly,

        -- * Deterministic Var environments (maps)
        DVarEnv, DIdEnv, DTyVarEnv,

        -- ** Manipulating these environments
        emptyDVarEnv, mkDVarEnv,
        dVarEnvElts,
        extendDVarEnv, extendDVarEnv_C,
        extendDVarEnvList,
        lookupDVarEnv, elemDVarEnv,
        isEmptyDVarEnv, foldDVarEnv, nonDetStrictFoldDVarEnv,
        mapDVarEnv, filterDVarEnv,
        modifyDVarEnv,
        alterDVarEnv,
        plusDVarEnv, plusDVarEnv_C,
        unitDVarEnv,
        delDVarEnv,
        delDVarEnvList,
        minusDVarEnv,
        partitionDVarEnv,
        anyDVarEnv,

        -- * The InScopeSet type
        InScopeSet(..),

        -- ** Operations on InScopeSets
        emptyInScopeSet, mkInScopeSet, mkInScopeSetList, delInScopeSet,
        extendInScopeSet, extendInScopeSetList, extendInScopeSetSet,
        getInScopeVars, lookupInScope, lookupInScope_Directly,
        unionInScope, elemInScopeSet, uniqAway,
        varSetInScope,
        unsafeGetFreshLocalUnique,

        -- * The RnEnv2 type
        RnEnv2,

        -- ** Operations on RnEnv2s
        mkRnEnv2, rnBndr2, rnBndrs2, rnBndr2_var,
        rnOccL, rnOccR, inRnEnvL, inRnEnvR,  anyInRnEnvR,
        rnOccL_maybe, rnOccR_maybe,
        rnBndrL, rnBndrR, nukeRnEnvL, nukeRnEnvR, rnSwap,
        delBndrL, delBndrR, delBndrsL, delBndrsR,
        extendRnInScopeSetList,
        rnEtaL, rnEtaR,
        rnInScope, rnInScopeSet, lookupRnInScope,
        rnEnvL, rnEnvR,

        -- * TidyEnv and its operation
        TidyEnv,
        emptyTidyEnv, mkEmptyTidyEnv, delTidyEnvList
    ) where

import GHC.Prelude
import qualified GHC.Data.Word64Map.Strict as Word64Map -- TODO: Move this to UniqFM

import GHC.Types.Name.Occurrence
import GHC.Types.Name
import GHC.Types.Var as Var
import GHC.Types.Var.Set
import GHC.Data.Graph.UnVar   -- UnVarSet
import GHC.Types.Unique.Set
import GHC.Types.Unique.FM
import GHC.Types.Unique.DFM
import GHC.Types.Unique
import GHC.Utils.Misc
import GHC.Utils.Panic
import GHC.Data.Maybe
import GHC.Utils.Outputable

{-
************************************************************************
*                                                                      *
                In-scope sets
*                                                                      *
************************************************************************
-}

-- | A set of variables that are in scope at some point.
--
-- Note that this is a /superset/ of the variables that are currently in scope.
-- See Note [The InScopeSet invariant].
--
-- "Secrets of the Glasgow Haskell Compiler inliner" Section 3.2 provides
-- the motivation for this abstraction.
newtype InScopeSet = InScope VarSet
        -- Note [Lookups in in-scope set]
        -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        -- We store a VarSet here, but we use this for lookups rather than just
        -- membership tests. Typically the InScopeSet contains the canonical
        -- version of the variable (e.g. with an informative unfolding), so this
        -- lookup is useful (see, for instance, Note [In-scope set as a
        -- substitution]).

        -- Note [The InScopeSet invariant]
        -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        -- The InScopeSet must include every in-scope variable, but it may also
        -- include other variables.

        -- Its principal purpose is to provide a set of variables to be avoided
        -- when creating a fresh identifier (fresh in the sense that it does not
        -- "shadow" any in-scope binding). To do this we simply have to find one that
        -- does not appear in the InScopeSet. This is done by the key function
        -- GHC.Types.Var.Env.uniqAway.

        -- See "Secrets of the Glasgow Haskell Compiler inliner" Section 3.2
        -- for more detailed motivation. #20419 has further discussion.


instance Outputable InScopeSet where
  ppr :: InScopeSet -> SDoc
ppr (InScope VarSet
s) =
    String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"InScope" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+>
    SDoc -> SDoc
forall doc. IsLine doc => doc -> doc
braces ([SDoc] -> SDoc
forall doc. IsLine doc => [doc] -> doc
fsep ((Var -> SDoc) -> [Var] -> [SDoc]
forall a b. (a -> b) -> [a] -> [b]
map (Name -> SDoc
forall a. Outputable a => a -> SDoc
ppr (Name -> SDoc) -> (Var -> Name) -> Var -> SDoc
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Var -> Name
Var.varName) (VarSet -> [Var]
forall elt. UniqSet elt -> [elt]
nonDetEltsUniqSet VarSet
s)))
                      -- It's OK to use nonDetEltsUniqSet here because it's
                      -- only for pretty printing
                      -- In-scope sets get big, and with -dppr-debug
                      -- the output is overwhelming

emptyInScopeSet :: InScopeSet
emptyInScopeSet :: InScopeSet
emptyInScopeSet = VarSet -> InScopeSet
InScope VarSet
emptyVarSet

getInScopeVars ::  InScopeSet -> VarSet
getInScopeVars :: InScopeSet -> VarSet
getInScopeVars (InScope VarSet
vs) = VarSet
vs

mkInScopeSet :: VarSet -> InScopeSet
mkInScopeSet :: VarSet -> InScopeSet
mkInScopeSet VarSet
in_scope = VarSet -> InScopeSet
InScope VarSet
in_scope

mkInScopeSetList :: [Var] -> InScopeSet
mkInScopeSetList :: [Var] -> InScopeSet
mkInScopeSetList [Var]
vs = VarSet -> InScopeSet
InScope ([Var] -> VarSet
mkVarSet [Var]
vs)

extendInScopeSet :: InScopeSet -> Var -> InScopeSet
extendInScopeSet :: InScopeSet -> Var -> InScopeSet
extendInScopeSet (InScope VarSet
in_scope) Var
v
   = VarSet -> InScopeSet
InScope (VarSet -> Var -> VarSet
extendVarSet VarSet
in_scope Var
v)

extendInScopeSetList :: InScopeSet -> [Var] -> InScopeSet
extendInScopeSetList :: InScopeSet -> [Var] -> InScopeSet
extendInScopeSetList (InScope VarSet
in_scope) [Var]
vs
   = VarSet -> InScopeSet
InScope (VarSet -> InScopeSet) -> VarSet -> InScopeSet
forall a b. (a -> b) -> a -> b
$ (VarSet -> Var -> VarSet) -> VarSet -> [Var] -> VarSet
forall b a. (b -> a -> b) -> b -> [a] -> b
forall (t :: * -> *) b a.
Foldable t =>
(b -> a -> b) -> b -> t a -> b
foldl' VarSet -> Var -> VarSet
extendVarSet VarSet
in_scope [Var]
vs

extendInScopeSetSet :: InScopeSet -> VarSet -> InScopeSet
extendInScopeSetSet :: InScopeSet -> VarSet -> InScopeSet
extendInScopeSetSet (InScope VarSet
in_scope) VarSet
vs
   = VarSet -> InScopeSet
InScope (VarSet
in_scope VarSet -> VarSet -> VarSet
`unionVarSet` VarSet
vs)

delInScopeSet :: InScopeSet -> Var -> InScopeSet
delInScopeSet :: InScopeSet -> Var -> InScopeSet
delInScopeSet (InScope VarSet
in_scope) Var
v = VarSet -> InScopeSet
InScope (VarSet
in_scope VarSet -> Var -> VarSet
`delVarSet` Var
v)

elemInScopeSet :: Var -> InScopeSet -> Bool
elemInScopeSet :: Var -> InScopeSet -> Bool
elemInScopeSet Var
v (InScope VarSet
in_scope) = Var
v Var -> VarSet -> Bool
`elemVarSet` VarSet
in_scope

-- | Look up a variable the 'InScopeSet'.  This lets you map from
-- the variable's identity (unique) to its full value.
lookupInScope :: InScopeSet -> Var -> Maybe Var
lookupInScope :: InScopeSet -> Var -> Maybe Var
lookupInScope (InScope VarSet
in_scope) Var
v  = VarSet -> Var -> Maybe Var
lookupVarSet VarSet
in_scope Var
v

lookupInScope_Directly :: InScopeSet -> Unique -> Maybe Var
lookupInScope_Directly :: InScopeSet -> Unique -> Maybe Var
lookupInScope_Directly (InScope VarSet
in_scope) Unique
uniq
  = VarSet -> Unique -> Maybe Var
lookupVarSet_Directly VarSet
in_scope Unique
uniq

unionInScope :: InScopeSet -> InScopeSet -> InScopeSet
unionInScope :: InScopeSet -> InScopeSet -> InScopeSet
unionInScope (InScope VarSet
s1) (InScope VarSet
s2)
  = VarSet -> InScopeSet
InScope (VarSet
s1 VarSet -> VarSet -> VarSet
`unionVarSet` VarSet
s2)

varSetInScope :: VarSet -> InScopeSet -> Bool
varSetInScope :: VarSet -> InScopeSet -> Bool
varSetInScope VarSet
vars (InScope VarSet
s1) = VarSet
vars VarSet -> VarSet -> Bool
`subVarSet` VarSet
s1

{-
Note [Local uniques]
~~~~~~~~~~~~~~~~~~~~
Sometimes one must create conjure up a unique which is unique in a particular
context (but not necessarily globally unique). For instance, one might need to
create a fresh local identifier which does not shadow any of the locally
in-scope variables.  For this we purpose we provide 'uniqAway'.

'uniqAway' is implemented in terms of the 'unsafeGetFreshLocalUnique'
operation, which generates an unclaimed 'Unique' from an 'InScopeSet'. To
ensure that we do not conflict with uniques allocated by future allocations
from 'UniqSupply's, Uniques generated by 'unsafeGetFreshLocalUnique' are
allocated into a dedicated region of the unique space (namely the X tag).

Note that one must be quite carefully when using uniques generated in this way
since they are only locally unique. In particular, two successive calls to
'uniqAway' on the same 'InScopeSet' will produce the same unique.
 -}

-- | @uniqAway in_scope v@ finds a unique that is not used in the
-- in-scope set, and gives that to v. See Note [Local uniques] and
-- Note [The InScopeSet invariant].
uniqAway :: InScopeSet -> Var -> Var
-- It starts with v's current unique, of course, in the hope that it won't
-- have to change, and thereafter uses the successor to the last derived unique
-- found in the in-scope set.
uniqAway :: InScopeSet -> Var -> Var
uniqAway InScopeSet
in_scope Var
var
  | Var
var Var -> InScopeSet -> Bool
`elemInScopeSet` InScopeSet
in_scope = InScopeSet -> Var -> Var
uniqAway' InScopeSet
in_scope Var
var      -- Make a new one
  | Bool
otherwise                     = Var
var                         -- Nothing to do

uniqAway' :: InScopeSet -> Var -> Var
-- This one *always* makes up a new variable
uniqAway' :: InScopeSet -> Var -> Var
uniqAway' InScopeSet
in_scope Var
var
  = Var -> Unique -> Var
setVarUnique Var
var (InScopeSet -> Unique
unsafeGetFreshLocalUnique InScopeSet
in_scope)

-- | @unsafeGetFreshUnique in_scope@ finds a unique that is not in-scope in the
-- given 'InScopeSet'. This must be used very carefully since one can very easily
-- introduce non-unique 'Unique's this way. See Note [Local uniques].
unsafeGetFreshLocalUnique :: InScopeSet -> Unique
unsafeGetFreshLocalUnique :: InScopeSet -> Unique
unsafeGetFreshLocalUnique (InScope VarSet
set)
  | Just (Key
uniq,Var
_) <- Key -> Word64Map Var -> Maybe (Key, Var)
forall a. Key -> Word64Map a -> Maybe (Key, a)
Word64Map.lookupLT (Unique -> Key
getKey Unique
maxLocalUnique) (UniqFM Var Var -> Word64Map Var
forall {k} (key :: k) elt. UniqFM key elt -> Word64Map elt
ufmToIntMap (UniqFM Var Var -> Word64Map Var)
-> UniqFM Var Var -> Word64Map Var
forall a b. (a -> b) -> a -> b
$ VarSet -> UniqFM Var Var
forall a. UniqSet a -> UniqFM a a
getUniqSet VarSet
set)
  , let uniq' :: Unique
uniq' = Key -> Unique
mkLocalUnique Key
uniq
  , Bool -> Bool
not (Bool -> Bool) -> Bool -> Bool
forall a b. (a -> b) -> a -> b
$ Unique
uniq' Unique -> Unique -> Bool
`ltUnique` Unique
minLocalUnique
  = Unique -> Unique
incrUnique Unique
uniq'

  | Bool
otherwise
  = Unique
minLocalUnique

{-
************************************************************************
*                                                                      *
                Dual renaming
*                                                                      *
************************************************************************
-}

-- | Rename Environment 2
--
-- When we are comparing (or matching) types or terms, we are faced with
-- \"going under\" corresponding binders.  E.g. when comparing:
--
-- > \x. e1     ~   \y. e2
--
-- Basically we want to rename [@x@ -> @y@] or [@y@ -> @x@], but there are lots of
-- things we must be careful of.  In particular, @x@ might be free in @e2@, or
-- y in @e1@.  So the idea is that we come up with a fresh binder that is free
-- in neither, and rename @x@ and @y@ respectively.  That means we must maintain:
--
-- 1. A renaming for the left-hand expression
--
-- 2. A renaming for the right-hand expressions
--
-- 3. An in-scope set
--
-- Furthermore, when matching, we want to be able to have an 'occurs check',
-- to prevent:
--
-- > \x. f   ~   \y. y
--
-- matching with [@f@ -> @y@].  So for each expression we want to know that set of
-- locally-bound variables. That is precisely the domain of the mappings 1.
-- and 2., but we must ensure that we always extend the mappings as we go in.
--
-- All of this information is bundled up in the 'RnEnv2'
data RnEnv2
  = RV2 { RnEnv2 -> UniqFM Var Var
envL     :: VarEnv Var        -- Renaming for Left term
        , RnEnv2 -> UniqFM Var Var
envR     :: VarEnv Var        -- Renaming for Right term
        , RnEnv2 -> InScopeSet
in_scope :: InScopeSet }      -- In scope in left or right terms

-- The renamings envL and envR are *guaranteed* to contain a binding
-- for every variable bound as we go into the term, even if it is not
-- renamed.  That way we can ask what variables are locally bound
-- (inRnEnvL, inRnEnvR)

mkRnEnv2 :: InScopeSet -> RnEnv2
mkRnEnv2 :: InScopeSet -> RnEnv2
mkRnEnv2 InScopeSet
vars = RV2     { envL :: UniqFM Var Var
envL     = UniqFM Var Var
forall a. VarEnv a
emptyVarEnv
                        , envR :: UniqFM Var Var
envR     = UniqFM Var Var
forall a. VarEnv a
emptyVarEnv
                        , in_scope :: InScopeSet
in_scope = InScopeSet
vars }

extendRnInScopeSetList :: RnEnv2 -> [Var] -> RnEnv2
extendRnInScopeSetList :: RnEnv2 -> [Var] -> RnEnv2
extendRnInScopeSetList RnEnv2
env [Var]
vs
  | [Var] -> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [Var]
vs   = RnEnv2
env
  | Bool
otherwise = RnEnv2
env { in_scope = extendInScopeSetList (in_scope env) vs }

rnInScope :: Var -> RnEnv2 -> Bool
rnInScope :: Var -> RnEnv2 -> Bool
rnInScope Var
x RnEnv2
env = Var
x Var -> InScopeSet -> Bool
`elemInScopeSet` RnEnv2 -> InScopeSet
in_scope RnEnv2
env

rnInScopeSet :: RnEnv2 -> InScopeSet
rnInScopeSet :: RnEnv2 -> InScopeSet
rnInScopeSet = RnEnv2 -> InScopeSet
in_scope

-- | Retrieve the left mapping
rnEnvL :: RnEnv2 -> VarEnv Var
rnEnvL :: RnEnv2 -> UniqFM Var Var
rnEnvL = RnEnv2 -> UniqFM Var Var
envL

-- | Retrieve the right mapping
rnEnvR :: RnEnv2 -> VarEnv Var
rnEnvR :: RnEnv2 -> UniqFM Var Var
rnEnvR = RnEnv2 -> UniqFM Var Var
envR

rnBndrs2 :: RnEnv2 -> [Var] -> [Var] -> RnEnv2
-- ^ Applies 'rnBndr2' to several variables: the two variable lists must be of equal length
rnBndrs2 :: RnEnv2 -> [Var] -> [Var] -> RnEnv2
rnBndrs2 RnEnv2
env [Var]
bsL [Var]
bsR = (RnEnv2 -> Var -> Var -> RnEnv2)
-> RnEnv2 -> [Var] -> [Var] -> RnEnv2
forall acc a b. (acc -> a -> b -> acc) -> acc -> [a] -> [b] -> acc
foldl2 RnEnv2 -> Var -> Var -> RnEnv2
rnBndr2 RnEnv2
env [Var]
bsL [Var]
bsR

rnBndr2 :: RnEnv2 -> Var -> Var -> RnEnv2
-- ^ @rnBndr2 env bL bR@ goes under a binder @bL@ in the Left term,
--                       and binder @bR@ in the Right term.
-- It finds a new binder, @new_b@,
-- and returns an environment mapping @bL -> new_b@ and @bR -> new_b@
rnBndr2 :: RnEnv2 -> Var -> Var -> RnEnv2
rnBndr2 RnEnv2
env Var
bL Var
bR = (RnEnv2, Var) -> RnEnv2
forall a b. (a, b) -> a
fst ((RnEnv2, Var) -> RnEnv2) -> (RnEnv2, Var) -> RnEnv2
forall a b. (a -> b) -> a -> b
$ RnEnv2 -> Var -> Var -> (RnEnv2, Var)
rnBndr2_var RnEnv2
env Var
bL Var
bR

rnBndr2_var :: RnEnv2 -> Var -> Var -> (RnEnv2, Var)
-- ^ Similar to 'rnBndr2' but returns the new variable as well as the
-- new environment.
-- Postcondition: the type of the returned Var is that of bR
rnBndr2_var :: RnEnv2 -> Var -> Var -> (RnEnv2, Var)
rnBndr2_var (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
envL, envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
envR, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
bL Var
bR
  = (RV2 { envL :: UniqFM Var Var
envL     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envL Var
bL Var
new_b   -- See Note
         , envR :: UniqFM Var Var
envR     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envR Var
bR Var
new_b   -- [Rebinding]
         , in_scope :: InScopeSet
in_scope = InScopeSet -> Var -> InScopeSet
extendInScopeSet InScopeSet
in_scope Var
new_b }, Var
new_b)
  where
        -- Find a new binder not in scope in either term
        -- To avoid calling `uniqAway`, we try bL's Unique
        -- But we always return a Var whose type is that of bR
    new_b :: Var
new_b | Bool -> Bool
not (Var
bR Var -> InScopeSet -> Bool
`elemInScopeSet` InScopeSet
in_scope) = Var
bR
          | Bool -> Bool
not (Var
bL Var -> InScopeSet -> Bool
`elemInScopeSet` InScopeSet
in_scope) = Var
bR Var -> Unique -> Var
`setVarUnique` Var -> Unique
varUnique Var
bL
          | Bool
otherwise                          = InScopeSet -> Var -> Var
uniqAway' InScopeSet
in_scope Var
bR

        -- Note [Rebinding]
        -- ~~~~~~~~~~~~~~~~
        -- If the new var is the same as the old one, note that
        -- the extendVarEnv *replaces* any current renaming
        -- E.g.   (\x. \x. ...)  ~  (\y. \z. ...)
        --
        --                        envL    envR          in_scope
        --   Inside \x  \y      { [x->y], [y->y],       {y} }
        --          \x  \z      { [x->z], [y->y, z->z], {y,z} }
        --          The envL binding [x->y] is replaced by [x->z]

rnBndrL :: RnEnv2 -> Var -> (RnEnv2, Var)
-- ^ Similar to 'rnBndr2' but used when there's a binder on the left
-- side only.
rnBndrL :: RnEnv2 -> Var -> (RnEnv2, Var)
rnBndrL (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
envL, envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
envR, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
bL
  = (RV2 { envL :: UniqFM Var Var
envL     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envL Var
bL Var
new_b
         , envR :: UniqFM Var Var
envR     = UniqFM Var Var
envR
         , in_scope :: InScopeSet
in_scope = InScopeSet -> Var -> InScopeSet
extendInScopeSet InScopeSet
in_scope Var
new_b }, Var
new_b)
  where
    new_b :: Var
new_b = InScopeSet -> Var -> Var
uniqAway InScopeSet
in_scope Var
bL

rnBndrR :: RnEnv2 -> Var -> (RnEnv2, Var)
-- ^ Similar to 'rnBndr2' but used when there's a binder on the right
-- side only.
rnBndrR :: RnEnv2 -> Var -> (RnEnv2, Var)
rnBndrR (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
envL, envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
envR, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
bR
  = (RV2 { envR :: UniqFM Var Var
envR     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envR Var
bR Var
new_b
         , envL :: UniqFM Var Var
envL     = UniqFM Var Var
envL
         , in_scope :: InScopeSet
in_scope = InScopeSet -> Var -> InScopeSet
extendInScopeSet InScopeSet
in_scope Var
new_b }, Var
new_b)
  where
    new_b :: Var
new_b = InScopeSet -> Var -> Var
uniqAway InScopeSet
in_scope Var
bR

rnEtaL :: RnEnv2 -> Var -> (RnEnv2, Var)
-- ^ Similar to 'rnBndrL' but used for eta expansion
-- See Note [Eta expansion]
rnEtaL :: RnEnv2 -> Var -> (RnEnv2, Var)
rnEtaL (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
envL, envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
envR, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
bL
  = (RV2 { envL :: UniqFM Var Var
envL     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envL Var
bL Var
new_b
         , envR :: UniqFM Var Var
envR     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envR Var
new_b Var
new_b     -- Note [Eta expansion]
         , in_scope :: InScopeSet
in_scope = InScopeSet -> Var -> InScopeSet
extendInScopeSet InScopeSet
in_scope Var
new_b }, Var
new_b)
  where
    new_b :: Var
new_b = InScopeSet -> Var -> Var
uniqAway InScopeSet
in_scope Var
bL

rnEtaR :: RnEnv2 -> Var -> (RnEnv2, Var)
-- ^ Similar to 'rnBndr2' but used for eta expansion
-- See Note [Eta expansion]
rnEtaR :: RnEnv2 -> Var -> (RnEnv2, Var)
rnEtaR (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
envL, envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
envR, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
bR
  = (RV2 { envL :: UniqFM Var Var
envL     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envL Var
new_b Var
new_b     -- Note [Eta expansion]
         , envR :: UniqFM Var Var
envR     = UniqFM Var Var -> Var -> Var -> UniqFM Var Var
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv UniqFM Var Var
envR Var
bR Var
new_b
         , in_scope :: InScopeSet
in_scope = InScopeSet -> Var -> InScopeSet
extendInScopeSet InScopeSet
in_scope Var
new_b }, Var
new_b)
  where
    new_b :: Var
new_b = InScopeSet -> Var -> Var
uniqAway InScopeSet
in_scope Var
bR

delBndrL, delBndrR :: RnEnv2 -> Var -> RnEnv2
delBndrL :: RnEnv2 -> Var -> RnEnv2
delBndrL rn :: RnEnv2
rn@(RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
env, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
v
  = RnEnv2
rn { envL = env `delVarEnv` v, in_scope = in_scope `extendInScopeSet` v }
delBndrR :: RnEnv2 -> Var -> RnEnv2
delBndrR rn :: RnEnv2
rn@(RV2 { envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
env, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) Var
v
  = RnEnv2
rn { envR = env `delVarEnv` v, in_scope = in_scope `extendInScopeSet` v }

delBndrsL, delBndrsR :: RnEnv2 -> [Var] -> RnEnv2
delBndrsL :: RnEnv2 -> [Var] -> RnEnv2
delBndrsL rn :: RnEnv2
rn@(RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
env, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) [Var]
v
  = RnEnv2
rn { envL = env `delVarEnvList` v, in_scope = in_scope `extendInScopeSetList` v }
delBndrsR :: RnEnv2 -> [Var] -> RnEnv2
delBndrsR rn :: RnEnv2
rn@(RV2 { envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
env, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope }) [Var]
v
  = RnEnv2
rn { envR = env `delVarEnvList` v, in_scope = in_scope `extendInScopeSetList` v }

rnOccL, rnOccR :: RnEnv2 -> Var -> Var
-- ^ Look up the renaming of an occurrence in the left or right term
rnOccL :: RnEnv2 -> Var -> Var
rnOccL (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
env }) Var
v = UniqFM Var Var -> Var -> Maybe Var
forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv UniqFM Var Var
env Var
v Maybe Var -> Var -> Var
forall a. Maybe a -> a -> a
`orElse` Var
v
rnOccR :: RnEnv2 -> Var -> Var
rnOccR (RV2 { envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
env }) Var
v = UniqFM Var Var -> Var -> Maybe Var
forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv UniqFM Var Var
env Var
v Maybe Var -> Var -> Var
forall a. Maybe a -> a -> a
`orElse` Var
v

rnOccL_maybe, rnOccR_maybe :: RnEnv2 -> Var -> Maybe Var
-- ^ Look up the renaming of an occurrence in the left or right term
rnOccL_maybe :: RnEnv2 -> Var -> Maybe Var
rnOccL_maybe (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
env }) Var
v = UniqFM Var Var -> Var -> Maybe Var
forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv UniqFM Var Var
env Var
v
rnOccR_maybe :: RnEnv2 -> Var -> Maybe Var
rnOccR_maybe (RV2 { envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
env }) Var
v = UniqFM Var Var -> Var -> Maybe Var
forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv UniqFM Var Var
env Var
v

inRnEnvL, inRnEnvR :: RnEnv2 -> Var -> Bool
-- ^ Tells whether a variable is locally bound
inRnEnvL :: RnEnv2 -> Var -> Bool
inRnEnvL (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
env }) Var
v = Var
v Var -> UniqFM Var Var -> Bool
forall a. Var -> VarEnv a -> Bool
`elemVarEnv` UniqFM Var Var
env
inRnEnvR :: RnEnv2 -> Var -> Bool
inRnEnvR (RV2 { envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
env }) Var
v = Var
v Var -> UniqFM Var Var -> Bool
forall a. Var -> VarEnv a -> Bool
`elemVarEnv` UniqFM Var Var
env

-- | `anyInRnEnvR env set` == `any (inRnEnvR rn_env) (toList set)`
-- but lazy in the second argument if the right side of the env is empty.
anyInRnEnvR :: RnEnv2 -> VarSet -> Bool
anyInRnEnvR :: RnEnv2 -> VarSet -> Bool
anyInRnEnvR (RV2 { envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
env }) VarSet
vs
  -- Avoid allocating the predicate if we deal with an empty env.
  | UniqFM Var Var -> Bool
forall a. VarEnv a -> Bool
isEmptyVarEnv UniqFM Var Var
env = Bool
False
  | Bool
otherwise         = (Var -> Bool) -> VarSet -> Bool
anyVarSet (Var -> UniqFM Var Var -> Bool
forall a. Var -> VarEnv a -> Bool
`elemVarEnv` UniqFM Var Var
env) VarSet
vs

lookupRnInScope :: RnEnv2 -> Var -> Var
lookupRnInScope :: RnEnv2 -> Var -> Var
lookupRnInScope RnEnv2
env Var
v = InScopeSet -> Var -> Maybe Var
lookupInScope (RnEnv2 -> InScopeSet
in_scope RnEnv2
env) Var
v Maybe Var -> Var -> Var
forall a. Maybe a -> a -> a
`orElse` Var
v

nukeRnEnvL, nukeRnEnvR :: RnEnv2 -> RnEnv2
-- ^ Wipe the left or right side renaming
nukeRnEnvL :: RnEnv2 -> RnEnv2
nukeRnEnvL RnEnv2
env = RnEnv2
env { envL = emptyVarEnv }
nukeRnEnvR :: RnEnv2 -> RnEnv2
nukeRnEnvR RnEnv2
env = RnEnv2
env { envR = emptyVarEnv }

rnSwap :: RnEnv2 -> RnEnv2
-- ^ swap the meaning of left and right
rnSwap :: RnEnv2 -> RnEnv2
rnSwap (RV2 { envL :: RnEnv2 -> UniqFM Var Var
envL = UniqFM Var Var
envL, envR :: RnEnv2 -> UniqFM Var Var
envR = UniqFM Var Var
envR, in_scope :: RnEnv2 -> InScopeSet
in_scope = InScopeSet
in_scope })
  = RV2 { envL :: UniqFM Var Var
envL = UniqFM Var Var
envR, envR :: UniqFM Var Var
envR = UniqFM Var Var
envL, in_scope :: InScopeSet
in_scope = InScopeSet
in_scope }

{-
Note [Eta expansion]
~~~~~~~~~~~~~~~~~~~~
When matching
     (\x.M) ~ N
we rename x to x' with, where x' is not in scope in
either term.  Then we want to behave as if we'd seen
     (\x'.M) ~ (\x'.N x')
Since x' isn't in scope in N, the form (\x'. N x') doesn't
capture any variables in N.  But we must nevertheless extend
the envR with a binding [x' -> x'], to support the occurs check.
For example, if we don't do this, we can get silly matches like
        forall a.  (\y.a)  ~   v
succeeding with [a -> v y], which is bogus of course.


************************************************************************
*                                                                      *
                Tidying
*                                                                      *
************************************************************************
-}

-- | Tidy Environment
--
-- When tidying up print names, we keep a mapping of in-scope occ-names
-- (the 'TidyOccEnv') and a Var-to-Var of the current renamings
type TidyEnv = (TidyOccEnv, VarEnv Var)

emptyTidyEnv :: TidyEnv
emptyTidyEnv :: TidyEnv
emptyTidyEnv = (TidyOccEnv
emptyTidyOccEnv, UniqFM Var Var
forall a. VarEnv a
emptyVarEnv)

mkEmptyTidyEnv :: TidyOccEnv -> TidyEnv
mkEmptyTidyEnv :: TidyOccEnv -> TidyEnv
mkEmptyTidyEnv TidyOccEnv
occ_env = (TidyOccEnv
occ_env, UniqFM Var Var
forall a. VarEnv a
emptyVarEnv)

delTidyEnvList :: TidyEnv -> [Var] -> TidyEnv
delTidyEnvList :: TidyEnv -> [Var] -> TidyEnv
delTidyEnvList (TidyOccEnv
occ_env, UniqFM Var Var
var_env) [Var]
vs = (TidyOccEnv
occ_env', UniqFM Var Var
var_env')
  where
    occ_env' :: TidyOccEnv
occ_env' = TidyOccEnv
occ_env TidyOccEnv -> [FastString] -> TidyOccEnv
`delTidyOccEnvList` (Var -> FastString) -> [Var] -> [FastString]
forall a b. (a -> b) -> [a] -> [b]
map (OccName -> FastString
occNameFS (OccName -> FastString) -> (Var -> OccName) -> Var -> FastString
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Var -> OccName
forall a. NamedThing a => a -> OccName
getOccName) [Var]
vs
    var_env' :: UniqFM Var Var
var_env' = UniqFM Var Var
var_env UniqFM Var Var -> [Var] -> UniqFM Var Var
forall a. VarEnv a -> [Var] -> VarEnv a
`delVarEnvList` [Var]
vs

{-
************************************************************************
*                                                                      *
   VarEnv
*                                                                      *
************************************************************************
-}

-- We would like this to be `UniqFM Var elt`
-- but the code uses various key types.
-- So for now make it explicitly untyped

-- | Variable Environment
type VarEnv elt     = UniqFM Var elt

-- | Identifier Environment
type IdEnv elt      = UniqFM Id elt

-- | Type Variable Environment
type TyVarEnv elt   = UniqFM Var elt

-- | Type or Coercion Variable Environment
type TyCoVarEnv elt = UniqFM TyCoVar elt

-- | Coercion Variable Environment
type CoVarEnv elt   = UniqFM CoVar elt

emptyVarEnv       :: VarEnv a
mkVarEnv          :: [(Var, a)] -> VarEnv a
mkVarEnv_Directly :: [(Unique, a)] -> VarEnv a
zipVarEnv         :: [Var] -> [a] -> VarEnv a
unitVarEnv        :: Var -> a -> VarEnv a
alterVarEnv       :: (Maybe a -> Maybe a) -> VarEnv a -> Var -> VarEnv a
extendVarEnv      :: VarEnv a -> Var -> a -> VarEnv a
extendVarEnv_C    :: (a->a->a) -> VarEnv a -> Var -> a -> VarEnv a
extendVarEnv_Acc  :: (a->b->b) -> (a->b) -> VarEnv b -> Var -> a -> VarEnv b
plusVarEnv        :: VarEnv a -> VarEnv a -> VarEnv a
plusVarEnvList    :: [VarEnv a] -> VarEnv a
extendVarEnvList  :: VarEnv a -> [(Var, a)] -> VarEnv a
varEnvDomain      :: VarEnv elt -> UnVarSet

partitionVarEnv   :: (a -> Bool) -> VarEnv a -> (VarEnv a, VarEnv a)
-- | Only keep variables contained in the VarSet
restrictVarEnv    :: VarEnv a -> VarSet -> VarEnv a
delVarEnvList     :: VarEnv a -> [Var] -> VarEnv a
delVarEnv         :: VarEnv a -> Var -> VarEnv a
minusVarEnv       :: VarEnv a -> VarEnv b -> VarEnv a
plusVarEnv_C      :: (a -> a -> a) -> VarEnv a -> VarEnv a -> VarEnv a
plusVarEnv_CD     :: (a -> a -> a) -> VarEnv a -> a -> VarEnv a -> a -> VarEnv a
plusMaybeVarEnv_C :: (a -> a -> Maybe a) -> VarEnv a -> VarEnv a -> VarEnv a
mapVarEnv         :: (a -> b) -> VarEnv a -> VarEnv b
modifyVarEnv      :: (a -> a) -> VarEnv a -> Var -> VarEnv a

isEmptyVarEnv     :: VarEnv a -> Bool
lookupVarEnv      :: VarEnv a -> Var -> Maybe a
lookupVarEnv_Directly :: VarEnv a -> Unique -> Maybe a
filterVarEnv      :: (a -> Bool) -> VarEnv a -> VarEnv a
anyVarEnv         :: (elt -> Bool) -> UniqFM key elt -> Bool
lookupVarEnv_NF   :: VarEnv a -> Var -> a
lookupWithDefaultVarEnv :: VarEnv a -> a -> Var -> a
elemVarEnv        :: Var -> VarEnv a -> Bool
elemVarEnvByKey   :: Unique -> VarEnv a -> Bool
disjointVarEnv    :: VarEnv a -> VarEnv a -> Bool
nonDetStrictFoldVarEnv_Directly :: (Unique -> a -> r -> r) -> r -> VarEnv a -> r

elemVarEnv :: forall a. Var -> VarEnv a -> Bool
elemVarEnv       = Var -> UniqFM Var a -> Bool
forall key elt. Uniquable key => key -> UniqFM key elt -> Bool
elemUFM
elemVarEnvByKey :: forall a. Unique -> VarEnv a -> Bool
elemVarEnvByKey  = Unique -> UniqFM Var a -> Bool
forall {k} (key :: k) elt. Unique -> UniqFM key elt -> Bool
elemUFM_Directly
disjointVarEnv :: forall a. VarEnv a -> VarEnv a -> Bool
disjointVarEnv   = UniqFM Var a -> UniqFM Var a -> Bool
forall {k} (key :: k) elt1 elt2.
UniqFM key elt1 -> UniqFM key elt2 -> Bool
disjointUFM
alterVarEnv :: forall a. (Maybe a -> Maybe a) -> VarEnv a -> Var -> VarEnv a
alterVarEnv      = (Maybe a -> Maybe a) -> UniqFM Var a -> Var -> UniqFM Var a
forall key elt.
Uniquable key =>
(Maybe elt -> Maybe elt) -> UniqFM key elt -> key -> UniqFM key elt
alterUFM
extendVarEnv :: forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv     = UniqFM Var a -> Var -> a -> UniqFM Var a
forall key elt.
Uniquable key =>
UniqFM key elt -> key -> elt -> UniqFM key elt
addToUFM
extendVarEnv_C :: forall a. (a -> a -> a) -> VarEnv a -> Var -> a -> VarEnv a
extendVarEnv_C   = (a -> a -> a) -> UniqFM Var a -> Var -> a -> UniqFM Var a
forall key elt.
Uniquable key =>
(elt -> elt -> elt)
-> UniqFM key elt -> key -> elt -> UniqFM key elt
addToUFM_C
extendVarEnv_Acc :: forall a b.
(a -> b -> b) -> (a -> b) -> VarEnv b -> Var -> a -> VarEnv b
extendVarEnv_Acc = (a -> b -> b)
-> (a -> b) -> UniqFM Var b -> Var -> a -> UniqFM Var b
forall key elt elts.
Uniquable key =>
(elt -> elts -> elts)
-> (elt -> elts)
-> UniqFM key elts
-> key
-> elt
-> UniqFM key elts
addToUFM_Acc
extendVarEnvList :: forall a. VarEnv a -> [(Var, a)] -> VarEnv a
extendVarEnvList = UniqFM Var a -> [(Var, a)] -> UniqFM Var a
forall key elt.
Uniquable key =>
UniqFM key elt -> [(key, elt)] -> UniqFM key elt
addListToUFM
plusVarEnv_C :: forall a. (a -> a -> a) -> VarEnv a -> VarEnv a -> VarEnv a
plusVarEnv_C     = (a -> a -> a) -> UniqFM Var a -> UniqFM Var a -> UniqFM Var a
forall {k} elt (key :: k).
(elt -> elt -> elt)
-> UniqFM key elt -> UniqFM key elt -> UniqFM key elt
plusUFM_C
plusVarEnv_CD :: forall a.
(a -> a -> a) -> VarEnv a -> a -> VarEnv a -> a -> VarEnv a
plusVarEnv_CD    = (a -> a -> a)
-> UniqFM Var a -> a -> UniqFM Var a -> a -> UniqFM Var a
forall {k} elta eltb eltc (key :: k).
(elta -> eltb -> eltc)
-> UniqFM key elta
-> elta
-> UniqFM key eltb
-> eltb
-> UniqFM key eltc
plusUFM_CD
plusMaybeVarEnv_C :: forall a. (a -> a -> Maybe a) -> VarEnv a -> VarEnv a -> VarEnv a
plusMaybeVarEnv_C = (a -> a -> Maybe a) -> UniqFM Var a -> UniqFM Var a -> UniqFM Var a
forall {k} elt (key :: k).
(elt -> elt -> Maybe elt)
-> UniqFM key elt -> UniqFM key elt -> UniqFM key elt
plusMaybeUFM_C
delVarEnvList :: forall a. VarEnv a -> [Var] -> VarEnv a
delVarEnvList    = UniqFM Var a -> [Var] -> UniqFM Var a
forall key elt.
Uniquable key =>
UniqFM key elt -> [key] -> UniqFM key elt
delListFromUFM
delVarEnv :: forall a. VarEnv a -> Var -> VarEnv a
delVarEnv        = UniqFM Var a -> Var -> UniqFM Var a
forall key elt.
Uniquable key =>
UniqFM key elt -> key -> UniqFM key elt
delFromUFM
minusVarEnv :: forall a b. VarEnv a -> VarEnv b -> VarEnv a
minusVarEnv      = UniqFM Var a -> UniqFM Var b -> UniqFM Var a
forall {k} (key :: k) elt1 elt2.
UniqFM key elt1 -> UniqFM key elt2 -> UniqFM key elt1
minusUFM
plusVarEnv :: forall a. VarEnv a -> VarEnv a -> VarEnv a
plusVarEnv       = UniqFM Var a -> UniqFM Var a -> UniqFM Var a
forall {k} (key :: k) elt.
UniqFM key elt -> UniqFM key elt -> UniqFM key elt
plusUFM
plusVarEnvList :: forall a. [VarEnv a] -> VarEnv a
plusVarEnvList   = [UniqFM Var a] -> UniqFM Var a
forall {k} (key :: k) elt. [UniqFM key elt] -> UniqFM key elt
plusUFMList
-- lookupVarEnv is very hot (in part due to being called by substTyVar),
-- if it's not inlined than the mere allocation of the Just constructor causes
-- perf benchmarks to regress by 2% in some cases. See #21159, !7638 and containers#821
-- for some more explanation about what exactly went wrong.
{-# INLINE lookupVarEnv #-}
lookupVarEnv :: forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv     = UniqFM Var a -> Var -> Maybe a
forall key elt. Uniquable key => UniqFM key elt -> key -> Maybe elt
lookupUFM
lookupVarEnv_Directly :: forall a. VarEnv a -> Unique -> Maybe a
lookupVarEnv_Directly = UniqFM Var a -> Unique -> Maybe a
forall {k} (key :: k) elt. UniqFM key elt -> Unique -> Maybe elt
lookupUFM_Directly
filterVarEnv :: forall a. (a -> Bool) -> VarEnv a -> VarEnv a
filterVarEnv     = (a -> Bool) -> UniqFM Var a -> UniqFM Var a
forall {k} elt (key :: k).
(elt -> Bool) -> UniqFM key elt -> UniqFM key elt
filterUFM
anyVarEnv :: forall {k} elt (key :: k). (elt -> Bool) -> UniqFM key elt -> Bool
anyVarEnv        = (elt -> Bool) -> UniqFM key elt -> Bool
forall {k} elt (key :: k). (elt -> Bool) -> UniqFM key elt -> Bool
anyUFM
lookupWithDefaultVarEnv :: forall a. VarEnv a -> a -> Var -> a
lookupWithDefaultVarEnv = UniqFM Var a -> a -> Var -> a
forall key elt.
Uniquable key =>
UniqFM key elt -> elt -> key -> elt
lookupWithDefaultUFM
mapVarEnv :: forall a b. (a -> b) -> VarEnv a -> VarEnv b
mapVarEnv        = (a -> b) -> UniqFM Var a -> UniqFM Var b
forall {k} elt1 elt2 (key :: k).
(elt1 -> elt2) -> UniqFM key elt1 -> UniqFM key elt2
mapUFM
mkVarEnv :: forall a. [(Var, a)] -> VarEnv a
mkVarEnv         = [(Var, a)] -> UniqFM Var a
forall key elt. Uniquable key => [(key, elt)] -> UniqFM key elt
listToUFM
mkVarEnv_Directly :: forall a. [(Unique, a)] -> VarEnv a
mkVarEnv_Directly= [(Unique, a)] -> UniqFM Var a
forall {k} elt (key :: k). [(Unique, elt)] -> UniqFM key elt
listToUFM_Directly
emptyVarEnv :: forall a. VarEnv a
emptyVarEnv      = UniqFM Var a
forall {k} (key :: k) elt. UniqFM key elt
emptyUFM
unitVarEnv :: forall a. Var -> a -> VarEnv a
unitVarEnv       = Var -> a -> UniqFM Var a
forall key elt. Uniquable key => key -> elt -> UniqFM key elt
unitUFM
isEmptyVarEnv :: forall a. VarEnv a -> Bool
isEmptyVarEnv    = UniqFM Var a -> Bool
forall {k} (key :: k) elt. UniqFM key elt -> Bool
isNullUFM
partitionVarEnv :: forall a. (a -> Bool) -> VarEnv a -> (VarEnv a, VarEnv a)
partitionVarEnv  = (a -> Bool) -> UniqFM Var a -> (UniqFM Var a, UniqFM Var a)
forall {k} elt (key :: k).
(elt -> Bool) -> UniqFM key elt -> (UniqFM key elt, UniqFM key elt)
partitionUFM
varEnvDomain :: forall elt. VarEnv elt -> UnVarSet
varEnvDomain     = UniqFM Var elt -> UnVarSet
forall {k} (key :: k) elt. UniqFM key elt -> UnVarSet
domUFMUnVarSet
nonDetStrictFoldVarEnv_Directly :: forall a r. (Unique -> a -> r -> r) -> r -> VarEnv a -> r
nonDetStrictFoldVarEnv_Directly = (Unique -> a -> r -> r) -> r -> UniqFM Var a -> r
forall {k} elt a (key :: k).
(Unique -> elt -> a -> a) -> a -> UniqFM key elt -> a
nonDetStrictFoldUFM_Directly


restrictVarEnv :: forall a. VarEnv a -> VarSet -> VarEnv a
restrictVarEnv VarEnv a
env VarSet
vs = (Unique -> a -> Bool) -> VarEnv a -> VarEnv a
forall {k} elt (key :: k).
(Unique -> elt -> Bool) -> UniqFM key elt -> UniqFM key elt
filterUFM_Directly Unique -> a -> Bool
keep VarEnv a
env
  where
    keep :: Unique -> a -> Bool
keep Unique
u a
_ = Unique
u Unique -> VarSet -> Bool
`elemVarSetByKey` VarSet
vs

zipVarEnv :: forall a. [Var] -> [a] -> VarEnv a
zipVarEnv [Var]
tyvars [a]
tys   = [(Var, a)] -> VarEnv a
forall a. [(Var, a)] -> VarEnv a
mkVarEnv (String -> [Var] -> [a] -> [(Var, a)]
forall a b. HasDebugCallStack => String -> [a] -> [b] -> [(a, b)]
zipEqual String
"zipVarEnv" [Var]
tyvars [a]
tys)
lookupVarEnv_NF :: forall a. VarEnv a -> Var -> a
lookupVarEnv_NF VarEnv a
env Var
id = case VarEnv a -> Var -> Maybe a
forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv VarEnv a
env Var
id of
                         Just a
xx -> a
xx
                         Maybe a
Nothing -> String -> a
forall a. HasCallStack => String -> a
panic String
"lookupVarEnv_NF: Nothing"


{-
@modifyVarEnv@: Look up a thing in the VarEnv,
then mash it with the modify function, and put it back.
-}

modifyVarEnv :: forall a. (a -> a) -> VarEnv a -> Var -> VarEnv a
modifyVarEnv a -> a
mangle_fn VarEnv a
env Var
key
  = case (VarEnv a -> Var -> Maybe a
forall a. VarEnv a -> Var -> Maybe a
lookupVarEnv VarEnv a
env Var
key) of
      Maybe a
Nothing -> VarEnv a
env
      Just a
xx -> VarEnv a -> Var -> a -> VarEnv a
forall a. VarEnv a -> Var -> a -> VarEnv a
extendVarEnv VarEnv a
env Var
key (a -> a
mangle_fn a
xx)

modifyVarEnv_Directly :: (a -> a) -> UniqFM key a -> Unique -> UniqFM key a
modifyVarEnv_Directly :: forall {k} a (key :: k).
(a -> a) -> UniqFM key a -> Unique -> UniqFM key a
modifyVarEnv_Directly a -> a
mangle_fn UniqFM key a
env Unique
key
  = case (UniqFM key a -> Unique -> Maybe a
forall {k} (key :: k) elt. UniqFM key elt -> Unique -> Maybe elt
lookupUFM_Directly UniqFM key a
env Unique
key) of
      Maybe a
Nothing -> UniqFM key a
env
      Just a
xx -> UniqFM key a -> Unique -> a -> UniqFM key a
forall {k} (key :: k) elt.
UniqFM key elt -> Unique -> elt -> UniqFM key elt
addToUFM_Directly UniqFM key a
env Unique
key (a -> a
mangle_fn a
xx)

{-
************************************************************************
*                                                                      *
   Deterministic VarEnv (DVarEnv)
*                                                                      *
************************************************************************
-}
-- See Note [Deterministic UniqFM] in GHC.Types.Unique.DFM for explanation why we need
-- DVarEnv.

-- | Deterministic Variable Environment
type DVarEnv elt = UniqDFM Var elt

-- | Deterministic Identifier Environment
-- Sadly not always indexed by Id, but it is in the common case.
type DIdEnv elt = UniqDFM Var elt

-- | Deterministic Type Variable Environment
type DTyVarEnv elt = UniqDFM TyVar elt

emptyDVarEnv :: DVarEnv a
emptyDVarEnv :: forall a. DVarEnv a
emptyDVarEnv = UniqDFM Var a
forall {k} (key :: k) elt. UniqDFM key elt
emptyUDFM

dVarEnvElts :: DVarEnv a -> [a]
dVarEnvElts :: forall a. DVarEnv a -> [a]
dVarEnvElts = UniqDFM Var a -> [a]
forall {k} (key :: k) elt. UniqDFM key elt -> [elt]
eltsUDFM

mkDVarEnv :: [(Var, a)] -> DVarEnv a
mkDVarEnv :: forall a. [(Var, a)] -> DVarEnv a
mkDVarEnv = [(Var, a)] -> UniqDFM Var a
forall key elt. Uniquable key => [(key, elt)] -> UniqDFM key elt
listToUDFM

extendDVarEnv :: DVarEnv a -> Var -> a -> DVarEnv a
extendDVarEnv :: forall a. DVarEnv a -> Var -> a -> DVarEnv a
extendDVarEnv = UniqDFM Var a -> Var -> a -> UniqDFM Var a
forall key elt.
Uniquable key =>
UniqDFM key elt -> key -> elt -> UniqDFM key elt
addToUDFM

minusDVarEnv :: DVarEnv a -> DVarEnv a' -> DVarEnv a
minusDVarEnv :: forall a a'. DVarEnv a -> DVarEnv a' -> DVarEnv a
minusDVarEnv = UniqDFM Var a -> UniqDFM Var a' -> UniqDFM Var a
forall {k} (key :: k) elt1 elt2.
UniqDFM key elt1 -> UniqDFM key elt2 -> UniqDFM key elt1
minusUDFM

lookupDVarEnv :: DVarEnv a -> Var -> Maybe a
lookupDVarEnv :: forall a. DVarEnv a -> Var -> Maybe a
lookupDVarEnv = UniqDFM Var a -> Var -> Maybe a
forall key elt.
Uniquable key =>
UniqDFM key elt -> key -> Maybe elt
lookupUDFM

foldDVarEnv :: (a -> b -> b) -> b -> DVarEnv a -> b
foldDVarEnv :: forall a b. (a -> b -> b) -> b -> DVarEnv a -> b
foldDVarEnv = (a -> b -> b) -> b -> UniqDFM Var a -> b
forall {k} elt a (key :: k).
(elt -> a -> a) -> a -> UniqDFM key elt -> a
foldUDFM

-- See Note [Deterministic UniqFM] to learn about nondeterminism.
-- If you use this please provide a justification why it doesn't introduce
-- nondeterminism.
nonDetStrictFoldDVarEnv :: (a -> b -> b) -> b -> DVarEnv a -> b
nonDetStrictFoldDVarEnv :: forall a b. (a -> b -> b) -> b -> DVarEnv a -> b
nonDetStrictFoldDVarEnv = (a -> b -> b) -> b -> UniqDFM Var a -> b
forall {k} elt a (key :: k).
(elt -> a -> a) -> a -> UniqDFM key elt -> a
nonDetStrictFoldUDFM

mapDVarEnv :: (a -> b) -> DVarEnv a -> DVarEnv b
mapDVarEnv :: forall a b. (a -> b) -> DVarEnv a -> DVarEnv b
mapDVarEnv = (a -> b) -> UniqDFM Var a -> UniqDFM Var b
forall {k} elt1 elt2 (key :: k).
(elt1 -> elt2) -> UniqDFM key elt1 -> UniqDFM key elt2
mapUDFM

filterDVarEnv      :: (a -> Bool) -> DVarEnv a -> DVarEnv a
filterDVarEnv :: forall a. (a -> Bool) -> DVarEnv a -> DVarEnv a
filterDVarEnv = (a -> Bool) -> UniqDFM Var a -> UniqDFM Var a
forall {k} elt (key :: k).
(elt -> Bool) -> UniqDFM key elt -> UniqDFM key elt
filterUDFM

alterDVarEnv :: (Maybe a -> Maybe a) -> DVarEnv a -> Var -> DVarEnv a
alterDVarEnv :: forall a. (Maybe a -> Maybe a) -> DVarEnv a -> Var -> DVarEnv a
alterDVarEnv = (Maybe a -> Maybe a) -> UniqDFM Var a -> Var -> UniqDFM Var a
forall key elt.
Uniquable key =>
(Maybe elt -> Maybe elt)
-> UniqDFM key elt -> key -> UniqDFM key elt
alterUDFM

plusDVarEnv :: DVarEnv a -> DVarEnv a -> DVarEnv a
plusDVarEnv :: forall a. DVarEnv a -> DVarEnv a -> DVarEnv a
plusDVarEnv = UniqDFM Var a -> UniqDFM Var a -> UniqDFM Var a
forall {k} (key :: k) elt.
UniqDFM key elt -> UniqDFM key elt -> UniqDFM key elt
plusUDFM

plusDVarEnv_C :: (a -> a -> a) -> DVarEnv a -> DVarEnv a -> DVarEnv a
plusDVarEnv_C :: forall a. (a -> a -> a) -> DVarEnv a -> DVarEnv a -> DVarEnv a
plusDVarEnv_C = (a -> a -> a) -> UniqDFM Var a -> UniqDFM Var a -> UniqDFM Var a
forall {k} elt (key :: k).
(elt -> elt -> elt)
-> UniqDFM key elt -> UniqDFM key elt -> UniqDFM key elt
plusUDFM_C

unitDVarEnv :: Var -> a -> DVarEnv a
unitDVarEnv :: forall a. Var -> a -> DVarEnv a
unitDVarEnv = Var -> a -> UniqDFM Var a
forall key elt. Uniquable key => key -> elt -> UniqDFM key elt
unitUDFM

delDVarEnv :: DVarEnv a -> Var -> DVarEnv a
delDVarEnv :: forall a. DVarEnv a -> Var -> DVarEnv a
delDVarEnv = UniqDFM Var a -> Var -> UniqDFM Var a
forall key elt.
Uniquable key =>
UniqDFM key elt -> key -> UniqDFM key elt
delFromUDFM

delDVarEnvList :: DVarEnv a -> [Var] -> DVarEnv a
delDVarEnvList :: forall a. DVarEnv a -> [Var] -> DVarEnv a
delDVarEnvList = UniqDFM Var a -> [Var] -> UniqDFM Var a
forall key elt.
Uniquable key =>
UniqDFM key elt -> [key] -> UniqDFM key elt
delListFromUDFM

isEmptyDVarEnv :: DVarEnv a -> Bool
isEmptyDVarEnv :: forall a. DVarEnv a -> Bool
isEmptyDVarEnv = UniqDFM Var a -> Bool
forall {k} (key :: k) elt. UniqDFM key elt -> Bool
isNullUDFM

elemDVarEnv :: Var -> DVarEnv a -> Bool
elemDVarEnv :: forall a. Var -> DVarEnv a -> Bool
elemDVarEnv = Var -> UniqDFM Var a -> Bool
forall key elt. Uniquable key => key -> UniqDFM key elt -> Bool
elemUDFM

extendDVarEnv_C :: (a -> a -> a) -> DVarEnv a -> Var -> a -> DVarEnv a
extendDVarEnv_C :: forall a. (a -> a -> a) -> DVarEnv a -> Var -> a -> DVarEnv a
extendDVarEnv_C = (a -> a -> a) -> UniqDFM Var a -> Var -> a -> UniqDFM Var a
forall key elt.
Uniquable key =>
(elt -> elt -> elt)
-> UniqDFM key elt -> key -> elt -> UniqDFM key elt
addToUDFM_C

modifyDVarEnv :: (a -> a) -> DVarEnv a -> Var -> DVarEnv a
modifyDVarEnv :: forall a. (a -> a) -> DVarEnv a -> Var -> DVarEnv a
modifyDVarEnv a -> a
mangle_fn DVarEnv a
env Var
key
  = case (DVarEnv a -> Var -> Maybe a
forall a. DVarEnv a -> Var -> Maybe a
lookupDVarEnv DVarEnv a
env Var
key) of
      Maybe a
Nothing -> DVarEnv a
env
      Just a
xx -> DVarEnv a -> Var -> a -> DVarEnv a
forall a. DVarEnv a -> Var -> a -> DVarEnv a
extendDVarEnv DVarEnv a
env Var
key (a -> a
mangle_fn a
xx)

partitionDVarEnv :: (a -> Bool) -> DVarEnv a -> (DVarEnv a, DVarEnv a)
partitionDVarEnv :: forall a. (a -> Bool) -> DVarEnv a -> (DVarEnv a, DVarEnv a)
partitionDVarEnv = (a -> Bool) -> UniqDFM Var a -> (UniqDFM Var a, UniqDFM Var a)
forall {k} elt (key :: k).
(elt -> Bool)
-> UniqDFM key elt -> (UniqDFM key elt, UniqDFM key elt)
partitionUDFM

extendDVarEnvList :: DVarEnv a -> [(Var, a)] -> DVarEnv a
extendDVarEnvList :: forall a. DVarEnv a -> [(Var, a)] -> DVarEnv a
extendDVarEnvList = UniqDFM Var a -> [(Var, a)] -> UniqDFM Var a
forall key elt.
Uniquable key =>
UniqDFM key elt -> [(key, elt)] -> UniqDFM key elt
addListToUDFM

anyDVarEnv :: (a -> Bool) -> DVarEnv a -> Bool
anyDVarEnv :: forall a. (a -> Bool) -> DVarEnv a -> Bool
anyDVarEnv = (a -> Bool) -> UniqDFM Var a -> Bool
forall {k} elt (key :: k). (elt -> Bool) -> UniqDFM key elt -> Bool
anyUDFM