{-# LANGUAGE AllowAmbiguousTypes #-}
{-# LANGUAGE UndecidableInstances #-}

-- SPDX-License-Identifier: MPL-2.0 AND BSD-3-Clause

-- This Source Code Form is subject to the terms of the Mozilla Public
-- License, v. 2.0. If a copy of the MPL was not distributed with this
-- file, You can obtain one at https://mozilla.org/MPL/2.0/.

{- |
Copyright   :  (c) 2016 Allele Dev; 2017 Ixperta Solutions s.r.o.; 2017 Alexis King; 2024 Sayo Koyoneda
License     :  MPL-2.0 (see the LICENSE file) AND BSD-3-Clause (see the LICENSE.BSD3 file)
Maintainer  :  ymdfield@outlook.jp
Description :  Open unions (type-indexed co-products) for extensible first-order effects.

Implementation of an open union for first-order effects.

Importing this module allows unsafe access to the data structure of the open
union, so it should not usually be imported directly.

Based on [the open union in freer-simple](https://hackage.haskell.org/package/freer-simple-1.2.1.2/docs/Data-OpenUnion-Internal.html).
-}
module Data.Effect.OpenUnion.Internal.FO where

import Data.Coerce (coerce)
import Data.Effect (EffectF)
import Data.Effect.Key (type (#>))
import Data.Effect.OpenUnion.Internal (
    BundleUnder,
    Drop,
    ElemAt,
    ElemIndex,
    FindElem,
    IfKeyNotFound,
    IfNotFound,
    IsSuffixOf,
    KnownLength,
    Length,
    P (unP),
    PrefixLength,
    Reverse,
    Split,
    Strengthen,
    StrengthenN,
    StrengthenNUnder,
    StrengthenUnder,
    Take,
    WeakenN,
    WeakenNUnder,
    WeakenUnder,
    elemNo,
    prefixLen,
    reifyLength,
    strengthenMap,
    strengthenMapUnder,
    wordVal,
    type (++),
 )
import Data.Kind (Type)
import GHC.TypeNats (KnownNat, type (-))
import Unsafe.Coerce (unsafeCoerce)

-- | Open union for first-order effects.
data Union (es :: [EffectF]) (a :: Type) where
    Union
        :: {-# UNPACK #-} !Word
        -- ^ A natural number tag to identify the element of the union.
        -> e a
        -- ^ The data of the higher-order effect that is an element of the union.
        -> Union es a

{- | Takes a request of type @e :: 'EffectF'@, and injects it into the 'Union'.

Summand is assigning a specified 'Word' value, which is a position in the
type-list @(e ': es) :: 'EffectF'@.

__This function is unsafe.__

/O(1)/
-}
unsafeInj :: Word -> e a -> Union es a
unsafeInj :: forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
unsafeInj = Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union
{-# INLINE unsafeInj #-}

{- | Project a value of type @'Union' (e ': es) :: 'EffectF'@ into a possible
summand of the type @e :: 'EffectF'@. 'Nothing' means that @e :: 'EffectF'@ is not
the value stored in the @'Union' (e ': es) :: 'EffectF'@.

It is assumed that summand is stored in the 'Union' when the 'Word' value is
the same value as is stored in the 'Union'.

__This function is unsafe.__

/O(1)/
-}
unsafePrj :: Word -> Union es a -> Maybe (e a)
unsafePrj :: forall (es :: [* -> *]) a (e :: * -> *).
Word -> Union es a -> Maybe (e a)
unsafePrj Word
n (Union Word
n' e a
e)
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
n' = e a -> Maybe (e a)
forall a. a -> Maybe a
Just (e a -> e a
forall a b. a -> b
unsafeCoerce e a
e)
    | Bool
otherwise = Maybe (e a)
forall a. Maybe a
Nothing
{-# INLINE unsafePrj #-}

{- | A constraint that requires that a particular effect, @e@, is a member of
the type-level list @es@. This is used to parameterize an
'Control.Monad.Hefty.Eff' computation over an arbitrary list of first-order effects, so
long as @e@ is /somewhere/ in the list.

For example, a computation that only needs access to a cell of mutable state
containing an 'Integer' would likely use the following type:

@
'Data.Effect.State.State' 'Integer' t'Data.Effect.OpenUnion.<|' ef => 'Control.Monad.Hefty.Eff' eh ef ()
@
-}
class (FindElem e es) => Member (e :: EffectF) es where
    -- This type class is used for two following purposes:
    --

    -- * As a @Constraint@ it guarantees that @e :: 'EffectF'@ is a member of a

    --   type-list @es :: ['EffectF']@.
    --

    -- * Provides a way how to inject\/project @e :: 'EffectF'@ into\/from a 'Union',

    --   respectively.
    --
    -- Following law has to hold:
    --
    -- @
    -- 'prj' . 'inj' === 'Just'
    -- @

    -- | Takes a request of type @e :: 'EffectF'@, and injects it into the
    -- 'Union'.
    --
    -- /O(1)/
    inj :: e a -> Union es a

    -- | Project a value of type @'Union' (e ': es) :: 'EffectF'@ into a possible
    -- summand of the type @e :: 'EffectF'@. 'Nothing' means that @e :: 'EffectF'@ is
    -- not the value stored in the @'Union' (e ': es) :: 'EffectF'@.
    --
    -- /O(1)/
    prj :: Union es a -> Maybe (e a)

instance (FindElem e es, IfNotFound e es es) => Member e es where
    inj :: forall a. e a -> Union es a
inj = Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
unsafeInj (Word -> e a -> Union es a) -> Word -> e a -> Union es a
forall a b. (a -> b) -> a -> b
$ P e es -> Word
forall k (e :: k) (es :: [k]). P e es -> Word
unP (P e es
forall {k} (e :: k) (es :: [k]). FindElem e es => P e es
elemNo :: P e es)
    {-# INLINE inj #-}

    prj :: forall a. Union es a -> Maybe (e a)
prj = Word -> Union es a -> Maybe (e a)
forall (es :: [* -> *]) a (e :: * -> *).
Word -> Union es a -> Maybe (e a)
unsafePrj (Word -> Union es a -> Maybe (e a))
-> Word -> Union es a -> Maybe (e a)
forall a b. (a -> b) -> a -> b
$ P e es -> Word
forall k (e :: k) (es :: [k]). P e es -> Word
unP (P e es
forall {k} (e :: k) (es :: [k]). FindElem e es => P e es
elemNo :: P e es)
    {-# INLINE prj #-}

infix 3 <|
type (<|) = Member

type MemberBy key e es = (key #> e <| es, Lookup key es ~ key #> e, IfKeyNotFound key es es)

type family Lookup (key :: k) r :: EffectF where
    Lookup key (key #> e ': _) = key #> e
    Lookup key (_ ': r) = Lookup key r

{- | Orthogonal decomposition of a @'Union' (e ': es) :: 'EffectF'@. 'Right' value
is returned if the @'Union' (e ': es) :: 'EffectF'@ contains @e :: 'EffectF'@, and
'Left' when it doesn't. Notice that 'Left' value contains
@'Union' es :: 'EffectF'@, i.e. it can not contain @e :: 'EffectF'@.

/O(1)/
-}
decomp :: Union (e ': es) a -> Either (Union es a) (e a)
decomp :: forall (e :: * -> *) (es :: [* -> *]) a.
Union (e : es) a -> Either (Union es a) (e a)
decomp (Union Word
0 e a
a) = e a -> Either (Union es a) (e a)
forall a b. b -> Either a b
Right (e a -> Either (Union es a) (e a))
-> e a -> Either (Union es a) (e a)
forall a b. (a -> b) -> a -> b
$ e a -> e a
forall a b. a -> b
unsafeCoerce e a
a
decomp (Union Word
n e a
a) = Union es a -> Either (Union es a) (e a)
forall a b. a -> Either a b
Left (Union es a -> Either (Union es a) (e a))
-> Union es a -> Either (Union es a) (e a)
forall a b. (a -> b) -> a -> b
$ Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
1) e a
a
{-# INLINE [2] decomp #-}

{- | Specialized version of 'decomp' for efficiency.

/O(1)/
-}

-- TODO: Check that it actually adds on efficiency.
decomp0 :: Union '[e] a -> Either (Union '[] a) (e a)
decomp0 :: forall (e :: * -> *) a. Union '[e] a -> Either (Union '[] a) (e a)
decomp0 (Union Word
_ e a
a) = e a -> Either (Union '[] a) (e a)
forall a b. b -> Either a b
Right (e a -> Either (Union '[] a) (e a))
-> e a -> Either (Union '[] a) (e a)
forall a b. (a -> b) -> a -> b
$ e a -> e a
forall a b. a -> b
unsafeCoerce e a
a
{-# INLINE decomp0 #-}

{-# RULES "decomp/singleton" decomp = decomp0 #-}

infixr 5 !+
(!+) :: (e a -> r) -> (Union es a -> r) -> Union (e : es) a -> r
(e a -> r
f !+ :: forall (e :: * -> *) a r (es :: [* -> *]).
(e a -> r) -> (Union es a -> r) -> Union (e : es) a -> r
!+ Union es a -> r
g) Union (e : es) a
u = case Union (e : es) a -> Either (Union es a) (e a)
forall (e :: * -> *) (es :: [* -> *]) a.
Union (e : es) a -> Either (Union es a) (e a)
decomp Union (e : es) a
u of
    Left Union es a
x -> Union es a -> r
g Union es a
x
    Right e a
x -> e a -> r
f e a
x
{-# INLINE (!+) #-}

{- | Specialised version of 'prj'\/'decomp' that works on an
@'Union' '[e] :: 'EffectF'@ which contains only one specific summand. Hence the
absence of 'Maybe', and 'Either'.

/O(1)/
-}
extract :: Union '[e] a -> e a
extract :: forall (e :: * -> *) a. Union '[e] a -> e a
extract (Union Word
_ e a
a) = e a -> e a
forall a b. a -> b
unsafeCoerce e a
a
{-# INLINE extract #-}

inj0 :: forall e es a. e a -> Union (e ': es) a
inj0 :: forall (e :: * -> *) (es :: [* -> *]) a. e a -> Union (e : es) a
inj0 = Word -> e a -> Union (e : es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union Word
0
{-# INLINE inj0 #-}

injN :: forall i es a. (KnownNat i) => ElemAt i es a -> Union es a
injN :: forall (i :: Nat) (es :: [* -> *]) a.
KnownNat i =>
ElemAt i es a -> Union es a
injN = Word -> ElemAt i es a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (forall (n :: Nat). KnownNat n => Word
wordVal @i)
{-# INLINE injN #-}

prjN :: forall i es a. (KnownNat i) => Union es a -> Maybe (ElemAt i es a)
prjN :: forall (i :: Nat) (es :: [* -> *]) a.
KnownNat i =>
Union es a -> Maybe (ElemAt i es a)
prjN (Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== forall (n :: Nat). KnownNat n => Word
wordVal @i = ElemAt i es a -> Maybe (ElemAt i es a)
forall a. a -> Maybe a
Just (ElemAt i es a -> Maybe (ElemAt i es a))
-> ElemAt i es a -> Maybe (ElemAt i es a)
forall a b. (a -> b) -> a -> b
$ e a -> ElemAt i es a
forall a b. a -> b
unsafeCoerce e a
a
    | Bool
otherwise = Maybe (ElemAt i es a)
forall a. Maybe a
Nothing
{-# INLINE prjN #-}

{- | Inject whole @'Union' es@ into a weaker @'Union' (any ': es)@ that has one
more summand.

/O(1)/
-}
weaken :: forall any es a. Union es a -> Union (any ': es) a
weaken :: forall (any :: * -> *) (es :: [* -> *]) a.
Union es a -> Union (any : es) a
weaken (Union Word
n e a
a) = Word -> e a -> Union (any : es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
1) e a
a
{-# INLINE weaken #-}

weakens :: forall es es' a. (es `IsSuffixOf` es') => Union es a -> Union es' a
weakens :: forall (es :: [* -> *]) (es' :: [* -> *]) a.
IsSuffixOf es es' =>
Union es a -> Union es' a
weakens (Union Word
n e a
a) = Word -> e a -> Union es' a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (es :: [* -> *]) (es' :: [* -> *]).
IsSuffixOf es es' =>
Word
forall {k} {k1} (es :: k) (es' :: k1). IsSuffixOf es es' => Word
prefixLen @es @es') e a
a
{-# INLINE weakens #-}

weakenN :: forall len es es' a. (WeakenN len es es') => Union es a -> Union es' a
weakenN :: forall (len :: Nat) (es :: [* -> *]) (es' :: [* -> *]) a.
WeakenN len es es' =>
Union es a -> Union es' a
weakenN (Union Word
n e a
a) = Word -> e a -> Union es' a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (n :: Nat). KnownNat n => Word
wordVal @len) e a
a
{-# INLINE weakenN #-}

weakenUnder :: forall any e es a. Union (e ': es) a -> Union (e ': any ': es) a
weakenUnder :: forall (any :: * -> *) (e :: * -> *) (es :: [* -> *]) a.
Union (e : es) a -> Union (e : any : es) a
weakenUnder u :: Union (e : es) a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
0 = Union (e : es) a -> Union (e : any : es) a
forall a b. Coercible a b => a -> b
coerce Union (e : es) a
u
    | Bool
otherwise = Word -> e a -> Union (e : any : es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
1) e a
a
{-# INLINE weakenUnder #-}

weakensUnder :: forall offset es es' a. (WeakenUnder offset es es') => Union es a -> Union es' a
weakensUnder :: forall (offset :: Nat) (es :: [* -> *]) (es' :: [* -> *]) a.
WeakenUnder offset es es' =>
Union es a -> Union es' a
weakensUnder = forall (len :: Nat) (offset :: Nat) (es :: [* -> *])
       (es' :: [* -> *]) a.
WeakenNUnder len offset es es' =>
Union es a -> Union es' a
weakenNUnder @(PrefixLength es es') @offset
{-# INLINE weakensUnder #-}

weakenNUnder
    :: forall len offset es es' a
     . (WeakenNUnder len offset es es')
    => Union es a
    -> Union es' a
weakenNUnder :: forall (len :: Nat) (offset :: Nat) (es :: [* -> *])
       (es' :: [* -> *]) a.
WeakenNUnder len offset es es' =>
Union es a -> Union es' a
weakenNUnder u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< forall (n :: Nat). KnownNat n => Word
wordVal @offset = Union es a -> Union es' a
forall a b. Coercible a b => a -> b
coerce Union es a
u
    | Bool
otherwise = Word -> e a -> Union es' a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (n :: Nat). KnownNat n => Word
wordVal @len) e a
a
{-# INLINE weakenNUnder #-}

strengthen :: forall e es a. (e <| es) => Union (e ': es) a -> Union es a
strengthen :: forall (e :: * -> *) (es :: [* -> *]) a.
(e <| es) =>
Union (e : es) a -> Union es a
strengthen (Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
0 = Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (forall (n :: Nat). KnownNat n => Word
wordVal @(ElemIndex e es)) e a
a
    | Bool
otherwise = Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
1) e a
a
{-# INLINE strengthen #-}

strengthens :: forall es es' a. (Strengthen es es') => Union es a -> Union es' a
strengthens :: forall (es :: [* -> *]) (es' :: [* -> *]) a.
Strengthen es es' =>
Union es a -> Union es' a
strengthens = forall (len :: Nat) (es :: [* -> *]) (es' :: [* -> *]) a.
StrengthenN len es es' =>
Union es a -> Union es' a
strengthenN @(PrefixLength es' es)
{-# INLINE strengthens #-}

strengthenN :: forall len es es' a. (StrengthenN len es es') => Union es a -> Union es' a
strengthenN :: forall (len :: Nat) (es :: [* -> *]) (es' :: [* -> *]) a.
StrengthenN len es es' =>
Union es a -> Union es' a
strengthenN (Union Word
n e a
a) = Word -> e a -> Union es' a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (forall k (isLenZero :: Bool) (len :: Nat) (es :: [k]) (es' :: [k]).
StrengthenMap_ isLenZero len es es' =>
Word -> Word
strengthenMap @_ @_ @len @es @es' Word
n) e a
a
{-# INLINE strengthenN #-}

strengthenUnder :: forall e2 e1 es a. (e2 <| es) => Union (e1 ': e2 ': es) a -> Union (e1 ': es) a
strengthenUnder :: forall (e2 :: * -> *) (e1 :: * -> *) (es :: [* -> *]) a.
(e2 <| es) =>
Union (e1 : e2 : es) a -> Union (e1 : es) a
strengthenUnder u :: Union (e1 : e2 : es) a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
0 = Union (e1 : e2 : es) a -> Union (e1 : es) a
forall a b. Coercible a b => a -> b
coerce Union (e1 : e2 : es) a
u
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
1 = Word -> e a -> Union (e1 : es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
1 Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (n :: Nat). KnownNat n => Word
wordVal @(ElemIndex e2 es)) e a
a
    | Bool
otherwise = Word -> e a -> Union (e1 : es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
1) e a
a
{-# INLINE strengthenUnder #-}

strengthensUnder :: forall offset es es' a. (StrengthenUnder offset es es') => Union es a -> Union es' a
strengthensUnder :: forall (offset :: Nat) (es :: [* -> *]) (es' :: [* -> *]) a.
StrengthenUnder offset es es' =>
Union es a -> Union es' a
strengthensUnder = forall (len :: Nat) (offset :: Nat) (es :: [* -> *])
       (es' :: [* -> *]) a.
StrengthenNUnder len offset es es' =>
Union es a -> Union es' a
strengthenNUnder @(PrefixLength es' es) @offset
{-# INLINE strengthensUnder #-}

strengthenNUnder
    :: forall len offset es es' a
     . (StrengthenNUnder len offset es es')
    => Union es a
    -> Union es' a
strengthenNUnder :: forall (len :: Nat) (offset :: Nat) (es :: [* -> *])
       (es' :: [* -> *]) a.
StrengthenNUnder len offset es es' =>
Union es a -> Union es' a
strengthenNUnder u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
off = Union es a -> Union es' a
forall a b. Coercible a b => a -> b
coerce Union es a
u
    | Bool
otherwise = Word -> e a -> Union es' a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
off Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (len :: Nat) (offset :: Nat) (es :: [* -> *])
       (es' :: [* -> *]).
StrengthenNUnder len offset es es' =>
Word -> Word
forall {k} (len :: Nat) (offset :: Nat) (es :: [k]) (es' :: [k]).
StrengthenNUnder len offset es es' =>
Word -> Word
strengthenMapUnder @len @offset @es @es' (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
off)) e a
a
  where
    off :: Word
off = forall (n :: Nat). KnownNat n => Word
wordVal @offset
{-# INLINE strengthenNUnder #-}

bundleUnion
    :: forall es bundle rest a
     . (Split es bundle rest)
    => Union es a
    -> Union (Union bundle ': rest) a
bundleUnion :: forall (es :: [* -> *]) (bundle :: [* -> *]) (rest :: [* -> *]) a.
Split es bundle rest =>
Union es a -> Union (Union bundle : rest) a
bundleUnion = forall (len :: Nat) (es :: [* -> *]) a.
KnownNat len =>
Union es a -> Union (Union (Take len es) : Drop len es) a
bundleUnionN @(Length bundle)

bundleUnionN
    :: forall len es a
     . (KnownNat len)
    => Union es a
    -> Union (Union (Take len es) ': Drop len es) a
bundleUnionN :: forall (len :: Nat) (es :: [* -> *]) a.
KnownNat len =>
Union es a -> Union (Union (Take len es) : Drop len es) a
bundleUnionN (Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
len = Word -> Union Any a -> Union (Union (Take len es) : Drop len es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union Word
0 (Union Any a -> Union (Union (Take len es) : Drop len es) a)
-> Union Any a -> Union (Union (Take len es) : Drop len es) a
forall a b. (a -> b) -> a -> b
$ Word -> e a -> Union Any a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union Word
n e a
a
    | Bool
otherwise = Word -> e a -> Union (Union (Take len es) : Drop len es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
len Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
1) e a
a
  where
    len :: Word
len = forall (n :: Nat). KnownNat n => Word
wordVal @len
{-# INLINE bundleUnionN #-}

unbundleUnion
    :: forall es bundle rest a
     . (Split es bundle rest)
    => Union (Union bundle ': rest) a
    -> Union es a
unbundleUnion :: forall (es :: [* -> *]) (bundle :: [* -> *]) (rest :: [* -> *]) a.
Split es bundle rest =>
Union (Union bundle : rest) a -> Union es a
unbundleUnion = forall (len :: Nat) (es :: [* -> *]) a.
KnownNat len =>
Union (Union (Take len es) : Drop len es) a -> Union es a
unbundleUnionN @(Length bundle)
{-# INLINE unbundleUnion #-}

unbundleUnionN
    :: forall len es a
     . (KnownNat len)
    => Union (Union (Take len es) ': Drop len es) a
    -> Union es a
unbundleUnionN :: forall (len :: Nat) (es :: [* -> *]) a.
KnownNat len =>
Union (Union (Take len es) : Drop len es) a -> Union es a
unbundleUnionN (Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
0 = e a -> Union es a
forall a b. a -> b
unsafeCoerce e a
a
    | Bool
otherwise = Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
1 Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (n :: Nat). KnownNat n => Word
wordVal @len) e a
a
{-# INLINE unbundleUnionN #-}

bundleUnionUnder
    :: forall offset bundle es es' a
     . (BundleUnder Union offset es es' bundle)
    => Union es a
    -> Union es' a
bundleUnionUnder :: forall (offset :: Nat) (bundle :: [* -> *]) (es :: [* -> *])
       (es' :: [* -> *]) a.
BundleUnder Union offset es es' bundle =>
Union es a -> Union es' a
bundleUnionUnder = forall (len :: Nat) (offset :: Nat) (es :: [* -> *]) a.
(KnownNat len, KnownNat offset) =>
Union es a
-> Union
     (Take offset es
      ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
     a
bundleUnionNUnder @(Length bundle) @offset
{-# INLINE bundleUnionUnder #-}

bundleUnionNUnder
    :: forall len offset es a
     . (KnownNat len, KnownNat offset)
    => Union es a
    -> Union (Take offset es ++ (Union (Take len (Drop offset es)) ': Drop len (Drop offset es))) a
bundleUnionNUnder :: forall (len :: Nat) (offset :: Nat) (es :: [* -> *]) a.
(KnownNat len, KnownNat offset) =>
Union es a
-> Union
     (Take offset es
      ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
     a
bundleUnionNUnder u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
off = Union es a
-> Union
     (Take offset es
      ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
     a
forall a b. Coercible a b => a -> b
coerce Union es a
u
    | Word
n' Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
len = Word
-> Union Any a
-> Union
     (Take offset es
      ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
     a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union Word
0 (Union Any a
 -> Union
      (Take offset es
       ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
      a)
-> Union Any a
-> Union
     (Take offset es
      ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
     a
forall a b. (a -> b) -> a -> b
$ Word -> e a -> Union Any a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union Word
n' e a
a
    | Bool
otherwise = Word
-> e a
-> Union
     (Take offset es
      ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
     a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
len Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
1) e a
a
  where
    off :: Word
off = forall (n :: Nat). KnownNat n => Word
wordVal @offset
    len :: Word
len = forall (n :: Nat). KnownNat n => Word
wordVal @len
    n' :: Word
n' = Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
off
{-# INLINE bundleUnionNUnder #-}

unbundleUnionUnder
    :: forall offset bundle es es' a
     . (BundleUnder Union offset es es' bundle)
    => Union es' a
    -> Union es a
unbundleUnionUnder :: forall (offset :: Nat) (bundle :: [* -> *]) (es :: [* -> *])
       (es' :: [* -> *]) a.
BundleUnder Union offset es es' bundle =>
Union es' a -> Union es a
unbundleUnionUnder = forall (len :: Nat) (offset :: Nat) (es :: [* -> *]) a.
(KnownNat len, KnownNat offset) =>
Union
  (Take offset es
   ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
  a
-> Union es a
unbundleUnionNUnder @(Length bundle) @offset
{-# INLINE unbundleUnionUnder #-}

unbundleUnionNUnder
    :: forall len offset es a
     . (KnownNat len, KnownNat offset)
    => Union (Take offset es ++ (Union (Take len (Drop offset es)) ': Drop len (Drop offset es))) a
    -> Union es a
unbundleUnionNUnder :: forall (len :: Nat) (offset :: Nat) (es :: [* -> *]) a.
(KnownNat len, KnownNat offset) =>
Union
  (Take offset es
   ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
  a
-> Union es a
unbundleUnionNUnder u :: Union
  (Take offset es
   ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
  a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
off = Union
  (Take offset es
   ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
  a
-> Union es a
forall a b. Coercible a b => a -> b
coerce Union
  (Take offset es
   ++ (Union (Take len (Drop offset es)) : Drop len (Drop offset es)))
  a
u
    | Word
n Word -> Word -> Bool
forall a. Eq a => a -> a -> Bool
== Word
off =
        case e a -> Union Any a
forall a b. a -> b
unsafeCoerce e a
a of
            Union Word
n' e a
a' -> Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
off Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
n') e a
a'
    | Bool
otherwise = Word -> e a -> Union es a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
1 Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
len) e a
a
  where
    off :: Word
off = forall (n :: Nat). KnownNat n => Word
wordVal @offset
    len :: Word
len = forall (n :: Nat). KnownNat n => Word
wordVal @len
{-# INLINE unbundleUnionNUnder #-}

bundleAllUnion :: Union es a -> Union '[Union es] a
bundleAllUnion :: forall (es :: [* -> *]) a. Union es a -> Union '[Union es] a
bundleAllUnion = Word -> Union es a -> Union '[Union es] a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union Word
0
{-# INLINE bundleAllUnion #-}

unbundleAllUnion :: Union '[Union es] a -> Union es a
unbundleAllUnion :: forall (es :: [* -> *]) a. Union '[Union es] a -> Union es a
unbundleAllUnion = Union '[Union es] a -> Union es a
forall (e :: * -> *) a. Union '[e] a -> e a
extract
{-# INLINE unbundleAllUnion #-}

prefixUnion :: forall any es a. (KnownLength any) => Union es a -> Union (any ++ es) a
prefixUnion :: forall (any :: [* -> *]) (es :: [* -> *]) a.
KnownLength any =>
Union es a -> Union (any ++ es) a
prefixUnion (Union Word
n e a
a) = Word -> e a -> Union (any ++ es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (es :: [* -> *]). KnownLength es => Word
forall {a} (es :: [a]). KnownLength es => Word
reifyLength @any) e a
a
{-# INLINE prefixUnion #-}

prefixUnionUnder
    :: forall any offset es a
     . (KnownLength any, KnownNat offset)
    => Union es a
    -> Union (Take offset es ++ any ++ Drop offset es) a
prefixUnionUnder :: forall (any :: [* -> *]) (offset :: Nat) (es :: [* -> *]) a.
(KnownLength any, KnownNat offset) =>
Union es a -> Union (Take offset es ++ (any ++ Drop offset es)) a
prefixUnionUnder u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< forall (n :: Nat). KnownNat n => Word
wordVal @offset = Union es a -> Union (Take offset es ++ (any ++ Drop offset es)) a
forall a b. Coercible a b => a -> b
coerce Union es a
u
    | Bool
otherwise = Word -> e a -> Union (Take offset es ++ (any ++ Drop offset es)) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (es :: [* -> *]). KnownLength es => Word
forall {a} (es :: [a]). KnownLength es => Word
reifyLength @any) e a
a
{-# INLINE prefixUnionUnder #-}

suffixUnion :: forall any es a. Union es a -> Union (es ++ any) a
suffixUnion :: forall (any :: [* -> *]) (es :: [* -> *]) a.
Union es a -> Union (es ++ any) a
suffixUnion = Union es a -> Union (es ++ any) a
forall a b. Coercible a b => a -> b
coerce
{-# INLINE suffixUnion #-}

suffixUnionOverN
    :: forall any offset es a
     . (KnownLength any, KnownNat offset, KnownLength es)
    => Union es a
    -> Union (Take (Length es - offset) es ++ any ++ Drop (Length es - offset) es) a
suffixUnionOverN :: forall (any :: [* -> *]) (offset :: Nat) (es :: [* -> *]) a.
(KnownLength any, KnownNat offset, KnownLength es) =>
Union es a
-> Union
     (Take (Length es - offset) es
      ++ (any ++ Drop (Length es - offset) es))
     a
suffixUnionOverN u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< forall (es :: [* -> *]). KnownLength es => Word
forall {a} (es :: [a]). KnownLength es => Word
reifyLength @es Word -> Word -> Word
forall a. Num a => a -> a -> a
- forall (n :: Nat). KnownNat n => Word
wordVal @offset = Union es a
-> Union
     (Take (Length es - offset) es
      ++ (any ++ Drop (Length es - offset) es))
     a
forall a b. Coercible a b => a -> b
coerce Union es a
u
    | Bool
otherwise = Word
-> e a
-> Union
     (Take (Length es - offset) es
      ++ (any ++ Drop (Length es - offset) es))
     a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
+ forall (es :: [* -> *]). KnownLength es => Word
forall {a} (es :: [a]). KnownLength es => Word
reifyLength @any) e a
a
{-# INLINE suffixUnionOverN #-}

flipAllUnion :: forall es a. (KnownLength es) => Union es a -> Union (Reverse es) a
flipAllUnion :: forall (es :: [* -> *]) a.
KnownLength es =>
Union es a -> Union (Reverse es) a
flipAllUnion (Union Word
n e a
a) = Word -> e a -> Union (Reverse_ '[] es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (forall (es :: [* -> *]). KnownLength es => Word
forall {a} (es :: [a]). KnownLength es => Word
reifyLength @es Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
n) e a
a
{-# INLINE flipAllUnion #-}

flipUnion
    :: forall len es a
     . (KnownNat len)
    => Union es a
    -> Union (Reverse (Take len es) ++ Drop len es) a
flipUnion :: forall (len :: Nat) (es :: [* -> *]) a.
KnownNat len =>
Union es a -> Union (Reverse (Take len es) ++ Drop len es) a
flipUnion u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
len = Word -> e a -> Union (Reverse_ '[] (Take len es) ++ Drop len es) a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
len Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
n) e a
a
    | Bool
otherwise = Union es a -> Union (Reverse_ '[] (Take len es) ++ Drop len es) a
forall a b. Coercible a b => a -> b
coerce Union es a
u
  where
    len :: Word
len = forall (n :: Nat). KnownNat n => Word
wordVal @len
{-# INLINE flipUnion #-}

flipUnionUnder
    :: forall len offset es a
     . (KnownNat len, KnownNat offset)
    => Union es a
    -> Union (Take offset es ++ Reverse (Take len (Drop offset es)) ++ Drop len (Drop offset es)) a
flipUnionUnder :: forall (len :: Nat) (offset :: Nat) (es :: [* -> *]) a.
(KnownNat len, KnownNat offset) =>
Union es a
-> Union
     (Take offset es
      ++ (Reverse (Take len (Drop offset es))
          ++ Drop len (Drop offset es)))
     a
flipUnionUnder u :: Union es a
u@(Union Word
n e a
a)
    | Word
n Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
>= Word
off Bool -> Bool -> Bool
&& Word
n' Word -> Word -> Bool
forall a. Ord a => a -> a -> Bool
< Word
len = Word
-> e a
-> Union
     (Take offset es
      ++ (Reverse_ '[] (Take len (Drop offset es))
          ++ Drop len (Drop offset es)))
     a
forall (e :: * -> *) a (es :: [* -> *]). Word -> e a -> Union es a
Union (Word
off Word -> Word -> Word
forall a. Num a => a -> a -> a
+ Word
len Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
n') e a
a
    | Bool
otherwise = Union es a
-> Union
     (Take offset es
      ++ (Reverse_ '[] (Take len (Drop offset es))
          ++ Drop len (Drop offset es)))
     a
forall a b. Coercible a b => a -> b
coerce Union es a
u
  where
    off :: Word
off = forall (n :: Nat). KnownNat n => Word
wordVal @offset
    len :: Word
len = forall (n :: Nat). KnownNat n => Word
wordVal @len
    n' :: Word
n' = Word
n Word -> Word -> Word
forall a. Num a => a -> a -> a
- Word
off
{-# INLINE flipUnionUnder #-}

nil :: Union '[] a -> r
nil :: forall a r. Union '[] a -> r
nil Union '[] a
_ = [Char] -> r
forall a. HasCallStack => [Char] -> a
error [Char]
"Effect system internal error: nil - An empty effect union, which should not be possible to create, has been created."