{-# LANGUAGE AllowAmbiguousTypes #-} -- For ShowLetName
{-# LANGUAGE BangPatterns #-} -- For makeSharingName
{-# LANGUAGE DataKinds #-} -- For ShowLetName
{-# LANGUAGE ExistentialQuantification #-} -- For SharingName
-- {-# LANGUAGE MagicHash #-} -- For unsafeCoerce#
module Symantic.ObserveSharing where

import Control.Applicative (Applicative(..))
import Control.Monad (Monad(..))
import Data.Bool
import Data.Eq (Eq(..))
import Data.Function (($), (.))
import Data.Functor (Functor, (<$>))
import Data.Functor.Compose (Compose(..))
import Data.HashMap.Strict (HashMap)
import Data.HashSet (HashSet)
import Data.Hashable (Hashable, hashWithSalt, hash)
import Data.Int (Int)
import Data.Maybe (Maybe(..), isNothing)
import Data.Monoid (Monoid(..))
import Data.Ord (Ord(..))
import Data.String (String)
-- import GHC.Exts (Int(..))
-- import GHC.Prim (unsafeCoerce#)
import GHC.StableName (StableName(..), makeStableName, hashStableName, eqStableName)
-- import Numeric (showHex)
import Prelude ((+), error)
import System.IO (IO)
import System.IO.Unsafe (unsafePerformIO)
import Text.Show (Show(..))
import qualified Control.Monad.Trans.Class as MT
import qualified Control.Monad.Trans.Reader as MT
import qualified Control.Monad.Trans.State as MT
import qualified Control.Monad.Trans.Writer as MT
import qualified Data.HashMap.Strict as HM
import qualified Data.HashSet as HS

import Symantic.Derive

-- * Class 'Referenceable'
-- | This class is not for end-users like usual symantic operators,
-- though it will have to be defined on end-users' interpreters.
class Referenceable letName repr where
  -- | @('ref' isRec letName)@ is a reference to @(letName)@.
  -- It is introduced by 'observeSharing'.
  -- @(isRec)@ is 'True' iif. this 'ref'erence is recursive,
  -- ie. appears within its 'def'inition.
  --
  -- TODO: index 'letName' with 'a' to enable dependent-map
  ref :: Bool -> letName -> repr a
  ref Bool
isRec letName
name = Derived repr a -> repr a
forall (repr :: * -> *) a.
LiftDerived repr =>
Derived repr a -> repr a
liftDerived (Bool -> letName -> Derived repr a
forall letName (repr :: * -> *) a.
Referenceable letName repr =>
Bool -> letName -> repr a
ref Bool
isRec letName
name)
  default ref ::
    FromDerived (Referenceable letName) repr =>
    Bool -> letName -> repr a

-- * Class 'Definable'
-- | This class is not for end-users like usual symantic operators.
-- There should be not need to use it outside this module,
-- because used 'def'initions are gathered in 'Letsable'.
class Definable letName repr where
  -- | @('def' letName sub)@ let-binds @(letName)@ to be equal to @(sub)@.
  -- This is a temporary node either replaced
  -- by 'ref' and an entry in 'lets''s 'LetBindings',
  -- or removed when no 'ref'erence is made to it.
  def :: letName -> repr a -> repr a
  def letName
name = (Derived repr a -> Derived repr a) -> repr a -> repr a
forall (repr :: * -> *) a b.
LiftDerived1 repr =>
(Derived repr a -> Derived repr b) -> repr a -> repr b
liftDerived1 (letName -> Derived repr a -> Derived repr a
forall letName (repr :: * -> *) a.
Definable letName repr =>
letName -> repr a -> repr a
def letName
name)
  default def ::
    FromDerived1 (Definable letName) repr =>
    letName -> repr a -> repr a

-- * Class 'MakeLetName'
class MakeLetName letName where
  makeLetName :: SharingName -> IO letName

-- * Type 'SharingName'
-- | Note that the observable sharing enabled by 'StableName'
-- is not perfect as it will not observe all the sharing explicitely done.
--
-- Note also that the observed sharing could be different between ghc and ghci.
data SharingName = forall a. SharingName (StableName a)
-- | @('makeSharingName' x)@ is like @('makeStableName' x)@ but it also forces
-- evaluation of @(x)@ to ensure that the 'StableName' is correct first time,
-- which avoids to produce a tree bigger than needed.
--
-- Note that this function uses 'unsafePerformIO' instead of returning in 'IO',
-- this is apparently required to avoid infinite loops due to unstable 'StableName'
-- in compiled code, and sometimes also in ghci.
--
-- Note that maybe [pseq should be used here](https://gitlab.haskell.org/ghc/ghc/-/issues/2916).
makeSharingName :: a -> SharingName
makeSharingName :: a -> SharingName
makeSharingName !a
x = StableName a -> SharingName
forall a. StableName a -> SharingName
SharingName (StableName a -> SharingName) -> StableName a -> SharingName
forall a b. (a -> b) -> a -> b
$ IO (StableName a) -> StableName a
forall a. IO a -> a
unsafePerformIO (IO (StableName a) -> StableName a)
-> IO (StableName a) -> StableName a
forall a b. (a -> b) -> a -> b
$ a -> IO (StableName a)
forall a. a -> IO (StableName a)
makeStableName a
x

instance Eq SharingName where
  SharingName StableName a
x == :: SharingName -> SharingName -> Bool
== SharingName StableName a
y = StableName a -> StableName a -> Bool
forall a b. StableName a -> StableName b -> Bool
eqStableName StableName a
x StableName a
y
instance Hashable SharingName where
  hash :: SharingName -> Int
hash (SharingName StableName a
n) = StableName a -> Int
forall a. StableName a -> Int
hashStableName StableName a
n
  hashWithSalt :: Int -> SharingName -> Int
hashWithSalt Int
salt (SharingName StableName a
n) = Int -> StableName a -> Int
forall a. Hashable a => Int -> a -> Int
hashWithSalt Int
salt StableName a
n
{-
instance Show SharingName where
  showsPrec _ (SharingName n) = showHex (I# (unsafeCoerce# n))
-}

-- * Type 'ObserveSharing'
newtype ObserveSharing letName repr a = ObserveSharing { ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ::
  MT.ReaderT (HashSet SharingName)
             (MT.State (ObserveSharingState letName))
             (FinalizeSharing letName repr a) }

-- | Interpreter detecting some (Haskell embedded) @let@ definitions used at
-- least once and/or recursively, in order to replace them
-- with the 'lets' and 'ref' combinators.
-- See [Type-safe observable sharing in Haskell](https://doi.org/10.1145/1596638.1596653)
--
-- Beware not to apply 'observeSharing' more than once on the same term
-- otherwise some 'def' introduced by the first call
-- would be removed by the second call.
observeSharing ::
  Eq letName =>
  Hashable letName =>
  Show letName =>
  ObserveSharing letName repr a ->
  WithSharing letName repr a
observeSharing :: ObserveSharing letName repr a -> WithSharing letName repr a
observeSharing (ObserveSharing ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
m) =
  let (FinalizeSharing letName repr a
fs, ObserveSharingState letName
st) = ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> HashSet SharingName
-> State
     (ObserveSharingState letName) (FinalizeSharing letName repr a)
forall r (m :: * -> *) a. ReaderT r m a -> r -> m a
MT.runReaderT ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
m HashSet SharingName
forall a. Monoid a => a
mempty State
  (ObserveSharingState letName) (FinalizeSharing letName repr a)
-> ObserveSharingState letName
-> (FinalizeSharing letName repr a, ObserveSharingState letName)
forall s a. State s a -> s -> (a, s)
`MT.runState`
        ObserveSharingState :: forall letName.
HashMap SharingName (letName, Int)
-> HashSet SharingName -> ObserveSharingState letName
ObserveSharingState
          { oss_refs :: HashMap SharingName (letName, Int)
oss_refs = HashMap SharingName (letName, Int)
forall k v. HashMap k v
HM.empty
          , oss_recs :: HashSet SharingName
oss_recs = HashSet SharingName
forall a. HashSet a
HS.empty
          } in
  let refs :: HashSet letName
refs = [letName] -> HashSet letName
forall a. (Eq a, Hashable a) => [a] -> HashSet a
HS.fromList
        [ letName
letName
        | (letName
letName, Int
refCount) <- HashMap SharingName (letName, Int) -> [(letName, Int)]
forall k v. HashMap k v -> [v]
HM.elems (ObserveSharingState letName -> HashMap SharingName (letName, Int)
forall letName.
ObserveSharingState letName -> HashMap SharingName (letName, Int)
oss_refs ObserveSharingState letName
st)
        , Int
refCount Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
> Int
0
        ] in
  --trace (show refs) $
  Writer (LetBindings letName repr) (repr a)
-> WithSharing letName repr a
forall w a. Writer w a -> (a, w)
MT.runWriter (Writer (LetBindings letName repr) (repr a)
 -> WithSharing letName repr a)
-> Writer (LetBindings letName repr) (repr a)
-> WithSharing letName repr a
forall a b. (a -> b) -> a -> b
$
  (ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> HashSet letName -> Writer (LetBindings letName repr) (repr a)
forall r (m :: * -> *) a. ReaderT r m a -> r -> m a
`MT.runReaderT` HashSet letName
refs) (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
 -> Writer (LetBindings letName repr) (repr a))
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> Writer (LetBindings letName repr) (repr a)
forall a b. (a -> b) -> a -> b
$
  FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
fs

-- ** Type 'WithSharing'
type WithSharing letName repr a =
  (repr a, HM.HashMap letName (SomeLet repr))
{-
-- * Type 'WithSharing'
data WithSharing letName repr a = WithSharing
  { lets :: HM.HashMap letName (SomeLet repr)
  , body :: repr a
  }
mapWithSharing ::
  (forall v. repr v -> repr v) ->
  WithSharing letName repr a ->
  WithSharing letName repr a
mapWithSharing f ws = WithSharing
  { lets = (\(SomeLet repr) -> SomeLet (f repr)) <$> lets ws
  , body = f (body ws)
  }
-}

-- ** Type 'ObserveSharingState'
data ObserveSharingState letName = ObserveSharingState
  { ObserveSharingState letName -> HashMap SharingName (letName, Int)
oss_refs :: HashMap SharingName (letName, Int)
  , ObserveSharingState letName -> HashSet SharingName
oss_recs :: HashSet SharingName
  }

observeSharingNode ::
  Eq letName =>
  Hashable letName =>
  Show letName =>
  Referenceable letName repr =>
  MakeLetName letName =>
  ObserveSharing letName repr a ->
  ObserveSharing letName repr a
observeSharingNode :: ObserveSharing letName repr a -> ObserveSharing letName repr a
observeSharingNode (ObserveSharing ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
m) = ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
ObserveSharing (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   (FinalizeSharing letName repr a)
 -> ObserveSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
forall a b. (a -> b) -> a -> b
$ do
  let nodeName :: SharingName
nodeName = ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> SharingName
forall a. a -> SharingName
makeSharingName ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
m
  ObserveSharingState letName
st <- StateT
  (ObserveSharingState letName)
  Identity
  (ObserveSharingState letName)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (ObserveSharingState letName)
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
MT.lift StateT
  (ObserveSharingState letName)
  Identity
  (ObserveSharingState letName)
forall (m :: * -> *) s. Monad m => StateT s m s
MT.get
  ((letName
letName, Maybe (letName, Int)
seenBefore), HashMap SharingName (letName, Int)
seen) <- Compose
  (ReaderT
     (HashSet SharingName) (State (ObserveSharingState letName)))
  ((,) (letName, Maybe (letName, Int)))
  (HashMap SharingName (letName, Int))
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     ((letName, Maybe (letName, Int)),
      HashMap SharingName (letName, Int))
forall k1 (f :: k1 -> *) k2 (g :: k2 -> k1) (a :: k2).
Compose f g a -> f (g a)
getCompose (Compose
   (ReaderT
      (HashSet SharingName) (State (ObserveSharingState letName)))
   ((,) (letName, Maybe (letName, Int)))
   (HashMap SharingName (letName, Int))
 -> ReaderT
      (HashSet SharingName)
      (State (ObserveSharingState letName))
      ((letName, Maybe (letName, Int)),
       HashMap SharingName (letName, Int)))
-> Compose
     (ReaderT
        (HashSet SharingName) (State (ObserveSharingState letName)))
     ((,) (letName, Maybe (letName, Int)))
     (HashMap SharingName (letName, Int))
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     ((letName, Maybe (letName, Int)),
      HashMap SharingName (letName, Int))
forall a b. (a -> b) -> a -> b
$ (Maybe (letName, Int)
 -> Compose
      (ReaderT
         (HashSet SharingName) (State (ObserveSharingState letName)))
      ((,) (letName, Maybe (letName, Int)))
      (Maybe (letName, Int)))
-> SharingName
-> HashMap SharingName (letName, Int)
-> Compose
     (ReaderT
        (HashSet SharingName) (State (ObserveSharingState letName)))
     ((,) (letName, Maybe (letName, Int)))
     (HashMap SharingName (letName, Int))
forall (f :: * -> *) k v.
(Functor f, Eq k, Hashable k) =>
(Maybe v -> f (Maybe v)) -> k -> HashMap k v -> f (HashMap k v)
HM.alterF (\Maybe (letName, Int)
seenBefore ->
    -- Compose is used to return (letName, seenBefore) along seen
    -- in the same HashMap lookup.
    ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  ((letName, Maybe (letName, Int)), Maybe (letName, Int))
-> Compose
     (ReaderT
        (HashSet SharingName) (State (ObserveSharingState letName)))
     ((,) (letName, Maybe (letName, Int)))
     (Maybe (letName, Int))
forall k k1 (f :: k -> *) (g :: k1 -> k) (a :: k1).
f (g a) -> Compose f g a
Compose (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   ((letName, Maybe (letName, Int)), Maybe (letName, Int))
 -> Compose
      (ReaderT
         (HashSet SharingName) (State (ObserveSharingState letName)))
      ((,) (letName, Maybe (letName, Int)))
      (Maybe (letName, Int)))
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     ((letName, Maybe (letName, Int)), Maybe (letName, Int))
-> Compose
     (ReaderT
        (HashSet SharingName) (State (ObserveSharingState letName)))
     ((,) (letName, Maybe (letName, Int)))
     (Maybe (letName, Int))
forall a b. (a -> b) -> a -> b
$ ((letName, Maybe (letName, Int)), Maybe (letName, Int))
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     ((letName, Maybe (letName, Int)), Maybe (letName, Int))
forall (m :: * -> *) a. Monad m => a -> m a
return (((letName, Maybe (letName, Int)), Maybe (letName, Int))
 -> ReaderT
      (HashSet SharingName)
      (State (ObserveSharingState letName))
      ((letName, Maybe (letName, Int)), Maybe (letName, Int)))
-> ((letName, Maybe (letName, Int)), Maybe (letName, Int))
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     ((letName, Maybe (letName, Int)), Maybe (letName, Int))
forall a b. (a -> b) -> a -> b
$ case Maybe (letName, Int)
seenBefore of
      Maybe (letName, Int)
Nothing ->
        ((letName
letName, Maybe (letName, Int)
seenBefore), (letName, Int) -> Maybe (letName, Int)
forall a. a -> Maybe a
Just (letName
letName, Int
0))
        where letName :: letName
letName = IO letName -> letName
forall a. IO a -> a
unsafePerformIO (IO letName -> letName) -> IO letName -> letName
forall a b. (a -> b) -> a -> b
$ SharingName -> IO letName
forall letName. MakeLetName letName => SharingName -> IO letName
makeLetName SharingName
nodeName
      Just (letName
letName, Int
refCount) ->
        ((letName
letName, Maybe (letName, Int)
seenBefore), (letName, Int) -> Maybe (letName, Int)
forall a. a -> Maybe a
Just (letName
letName, Int
refCount Int -> Int -> Int
forall a. Num a => a -> a -> a
+ Int
1))
    ) SharingName
nodeName (ObserveSharingState letName -> HashMap SharingName (letName, Int)
forall letName.
ObserveSharingState letName -> HashMap SharingName (letName, Int)
oss_refs ObserveSharingState letName
st)
  HashSet SharingName
parentNames <- ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (HashSet SharingName)
forall (m :: * -> *) r. Monad m => ReaderT r m r
MT.ask
  if SharingName
nodeName SharingName -> HashSet SharingName -> Bool
forall a. (Eq a, Hashable a) => a -> HashSet a -> Bool
`HS.member` HashSet SharingName
parentNames
  then do -- recursive reference to nodeName:
          -- update seen references
          -- and mark nodeName as recursive
    StateT (ObserveSharingState letName) Identity ()
-> ReaderT
     (HashSet SharingName) (State (ObserveSharingState letName)) ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
MT.lift (StateT (ObserveSharingState letName) Identity ()
 -> ReaderT
      (HashSet SharingName) (State (ObserveSharingState letName)) ())
-> StateT (ObserveSharingState letName) Identity ()
-> ReaderT
     (HashSet SharingName) (State (ObserveSharingState letName)) ()
forall a b. (a -> b) -> a -> b
$ ObserveSharingState letName
-> StateT (ObserveSharingState letName) Identity ()
forall (m :: * -> *) s. Monad m => s -> StateT s m ()
MT.put ObserveSharingState letName
st
      { oss_refs :: HashMap SharingName (letName, Int)
oss_refs = HashMap SharingName (letName, Int)
seen
      , oss_recs :: HashSet SharingName
oss_recs = SharingName -> HashSet SharingName -> HashSet SharingName
forall a. (Eq a, Hashable a) => a -> HashSet a -> HashSet a
HS.insert SharingName
nodeName (ObserveSharingState letName -> HashSet SharingName
forall letName. ObserveSharingState letName -> HashSet SharingName
oss_recs ObserveSharingState letName
st)
      }
    FinalizeSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall (m :: * -> *) a. Monad m => a -> m a
return (FinalizeSharing letName repr a
 -> ReaderT
      (HashSet SharingName)
      (State (ObserveSharingState letName))
      (FinalizeSharing letName repr a))
-> FinalizeSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall a b. (a -> b) -> a -> b
$ Bool -> letName -> FinalizeSharing letName repr a
forall letName (repr :: * -> *) a.
Referenceable letName repr =>
Bool -> letName -> repr a
ref Bool
True letName
letName
  else do -- non-recursive reference to nodeName
          -- update seen references
          -- and recurse if the nodeName hasn't been seen before
          -- (would be in a preceding sibling branch, not in parentNames).
    StateT (ObserveSharingState letName) Identity ()
-> ReaderT
     (HashSet SharingName) (State (ObserveSharingState letName)) ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
MT.lift (StateT (ObserveSharingState letName) Identity ()
 -> ReaderT
      (HashSet SharingName) (State (ObserveSharingState letName)) ())
-> StateT (ObserveSharingState letName) Identity ()
-> ReaderT
     (HashSet SharingName) (State (ObserveSharingState letName)) ()
forall a b. (a -> b) -> a -> b
$ ObserveSharingState letName
-> StateT (ObserveSharingState letName) Identity ()
forall (m :: * -> *) s. Monad m => s -> StateT s m ()
MT.put ObserveSharingState letName
st{ oss_refs :: HashMap SharingName (letName, Int)
oss_refs = HashMap SharingName (letName, Int)
seen }
    if Maybe (letName, Int) -> Bool
forall a. Maybe a -> Bool
isNothing Maybe (letName, Int)
seenBefore
      then (HashSet SharingName -> HashSet SharingName)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall r (m :: * -> *) a.
(r -> r) -> ReaderT r m a -> ReaderT r m a
MT.local (SharingName -> HashSet SharingName -> HashSet SharingName
forall a. (Eq a, Hashable a) => a -> HashSet a -> HashSet a
HS.insert SharingName
nodeName) (letName
-> FinalizeSharing letName repr a -> FinalizeSharing letName repr a
forall letName (repr :: * -> *) a.
Definable letName repr =>
letName -> repr a -> repr a
def letName
letName (FinalizeSharing letName repr a -> FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
m)
      else FinalizeSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall (m :: * -> *) a. Monad m => a -> m a
return (FinalizeSharing letName repr a
 -> ReaderT
      (HashSet SharingName)
      (State (ObserveSharingState letName))
      (FinalizeSharing letName repr a))
-> FinalizeSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall a b. (a -> b) -> a -> b
$ Bool -> letName -> FinalizeSharing letName repr a
forall letName (repr :: * -> *) a.
Referenceable letName repr =>
Bool -> letName -> repr a
ref Bool
False letName
letName

type instance Derived (ObserveSharing letName repr) = FinalizeSharing letName repr
instance
  ( Referenceable letName repr
  , MakeLetName letName
  , Eq letName
  , Hashable letName
  , Show letName
  ) => LiftDerived (ObserveSharing letName repr) where
  liftDerived :: Derived (ObserveSharing letName repr) a
-> ObserveSharing letName repr a
liftDerived = ObserveSharing letName repr a -> ObserveSharing letName repr a
forall letName (repr :: * -> *) a.
(Eq letName, Hashable letName, Show letName,
 Referenceable letName repr, MakeLetName letName) =>
ObserveSharing letName repr a -> ObserveSharing letName repr a
observeSharingNode (ObserveSharing letName repr a -> ObserveSharing letName repr a)
-> (FinalizeSharing letName repr a
    -> ObserveSharing letName repr a)
-> FinalizeSharing letName repr a
-> ObserveSharing letName repr a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
ObserveSharing (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   (FinalizeSharing letName repr a)
 -> ObserveSharing letName repr a)
-> (FinalizeSharing letName repr a
    -> ReaderT
         (HashSet SharingName)
         (State (ObserveSharingState letName))
         (FinalizeSharing letName repr a))
-> FinalizeSharing letName repr a
-> ObserveSharing letName repr a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. FinalizeSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall (m :: * -> *) a. Monad m => a -> m a
return
instance
  ( Referenceable letName repr
  , MakeLetName letName
  , Eq letName
  , Hashable letName
  , Show letName
  ) => LiftDerived1 (ObserveSharing letName repr) where
  liftDerived1 :: (Derived (ObserveSharing letName repr) a
 -> Derived (ObserveSharing letName repr) b)
-> ObserveSharing letName repr a -> ObserveSharing letName repr b
liftDerived1 Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
f ObserveSharing letName repr a
a = ObserveSharing letName repr b -> ObserveSharing letName repr b
forall letName (repr :: * -> *) a.
(Eq letName, Hashable letName, Show letName,
 Referenceable letName repr, MakeLetName letName) =>
ObserveSharing letName repr a -> ObserveSharing letName repr a
observeSharingNode (ObserveSharing letName repr b -> ObserveSharing letName repr b)
-> ObserveSharing letName repr b -> ObserveSharing letName repr b
forall a b. (a -> b) -> a -> b
$ ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr b)
-> ObserveSharing letName repr b
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
ObserveSharing (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   (FinalizeSharing letName repr b)
 -> ObserveSharing letName repr b)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
-> ObserveSharing letName repr b
forall a b. (a -> b) -> a -> b
$
    Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
FinalizeSharing letName repr a -> FinalizeSharing letName repr b
f (FinalizeSharing letName repr a -> FinalizeSharing letName repr b)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr a
a
instance
  ( Referenceable letName repr
  , MakeLetName letName
  , Eq letName
  , Hashable letName
  , Show letName
  ) => LiftDerived2 (ObserveSharing letName repr) where
  liftDerived2 :: (Derived (ObserveSharing letName repr) a
 -> Derived (ObserveSharing letName repr) b
 -> Derived (ObserveSharing letName repr) c)
-> ObserveSharing letName repr a
-> ObserveSharing letName repr b
-> ObserveSharing letName repr c
liftDerived2 Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
-> Derived (ObserveSharing letName repr) c
f ObserveSharing letName repr a
a ObserveSharing letName repr b
b = ObserveSharing letName repr c -> ObserveSharing letName repr c
forall letName (repr :: * -> *) a.
(Eq letName, Hashable letName, Show letName,
 Referenceable letName repr, MakeLetName letName) =>
ObserveSharing letName repr a -> ObserveSharing letName repr a
observeSharingNode (ObserveSharing letName repr c -> ObserveSharing letName repr c)
-> ObserveSharing letName repr c -> ObserveSharing letName repr c
forall a b. (a -> b) -> a -> b
$ ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr c)
-> ObserveSharing letName repr c
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
ObserveSharing (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   (FinalizeSharing letName repr c)
 -> ObserveSharing letName repr c)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c)
-> ObserveSharing letName repr c
forall a b. (a -> b) -> a -> b
$
    Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
-> Derived (ObserveSharing letName repr) c
FinalizeSharing letName repr a
-> FinalizeSharing letName repr b -> FinalizeSharing letName repr c
f (FinalizeSharing letName repr a
 -> FinalizeSharing letName repr b
 -> FinalizeSharing letName repr c)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b -> FinalizeSharing letName repr c)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr a
a
      ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr b -> FinalizeSharing letName repr c)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> ObserveSharing letName repr b
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr b
b
instance
  ( Referenceable letName repr
  , MakeLetName letName
  , Eq letName
  , Hashable letName
  , Show letName
  ) => LiftDerived3 (ObserveSharing letName repr) where
  liftDerived3 :: (Derived (ObserveSharing letName repr) a
 -> Derived (ObserveSharing letName repr) b
 -> Derived (ObserveSharing letName repr) c
 -> Derived (ObserveSharing letName repr) d)
-> ObserveSharing letName repr a
-> ObserveSharing letName repr b
-> ObserveSharing letName repr c
-> ObserveSharing letName repr d
liftDerived3 Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
-> Derived (ObserveSharing letName repr) c
-> Derived (ObserveSharing letName repr) d
f ObserveSharing letName repr a
a ObserveSharing letName repr b
b ObserveSharing letName repr c
c = ObserveSharing letName repr d -> ObserveSharing letName repr d
forall letName (repr :: * -> *) a.
(Eq letName, Hashable letName, Show letName,
 Referenceable letName repr, MakeLetName letName) =>
ObserveSharing letName repr a -> ObserveSharing letName repr a
observeSharingNode (ObserveSharing letName repr d -> ObserveSharing letName repr d)
-> ObserveSharing letName repr d -> ObserveSharing letName repr d
forall a b. (a -> b) -> a -> b
$ ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr d)
-> ObserveSharing letName repr d
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
ObserveSharing (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   (FinalizeSharing letName repr d)
 -> ObserveSharing letName repr d)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr d)
-> ObserveSharing letName repr d
forall a b. (a -> b) -> a -> b
$
    Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
-> Derived (ObserveSharing letName repr) c
-> Derived (ObserveSharing letName repr) d
FinalizeSharing letName repr a
-> FinalizeSharing letName repr b
-> FinalizeSharing letName repr c
-> FinalizeSharing letName repr d
f (FinalizeSharing letName repr a
 -> FinalizeSharing letName repr b
 -> FinalizeSharing letName repr c
 -> FinalizeSharing letName repr d)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b
      -> FinalizeSharing letName repr c
      -> FinalizeSharing letName repr d)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr a
a
      ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr b
   -> FinalizeSharing letName repr c
   -> FinalizeSharing letName repr d)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c -> FinalizeSharing letName repr d)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> ObserveSharing letName repr b
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr b
b
      ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr c -> FinalizeSharing letName repr d)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr d)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> ObserveSharing letName repr c
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr c
c
instance
  ( Referenceable letName repr
  , MakeLetName letName
  , Eq letName
  , Hashable letName
  , Show letName
  ) => LiftDerived4 (ObserveSharing letName repr) where
  liftDerived4 :: (Derived (ObserveSharing letName repr) a
 -> Derived (ObserveSharing letName repr) b
 -> Derived (ObserveSharing letName repr) c
 -> Derived (ObserveSharing letName repr) d
 -> Derived (ObserveSharing letName repr) e)
-> ObserveSharing letName repr a
-> ObserveSharing letName repr b
-> ObserveSharing letName repr c
-> ObserveSharing letName repr d
-> ObserveSharing letName repr e
liftDerived4 Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
-> Derived (ObserveSharing letName repr) c
-> Derived (ObserveSharing letName repr) d
-> Derived (ObserveSharing letName repr) e
f ObserveSharing letName repr a
a ObserveSharing letName repr b
b ObserveSharing letName repr c
c ObserveSharing letName repr d
d = ObserveSharing letName repr e -> ObserveSharing letName repr e
forall letName (repr :: * -> *) a.
(Eq letName, Hashable letName, Show letName,
 Referenceable letName repr, MakeLetName letName) =>
ObserveSharing letName repr a -> ObserveSharing letName repr a
observeSharingNode (ObserveSharing letName repr e -> ObserveSharing letName repr e)
-> ObserveSharing letName repr e -> ObserveSharing letName repr e
forall a b. (a -> b) -> a -> b
$ ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr e)
-> ObserveSharing letName repr e
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr a)
-> ObserveSharing letName repr a
ObserveSharing (ReaderT
   (HashSet SharingName)
   (State (ObserveSharingState letName))
   (FinalizeSharing letName repr e)
 -> ObserveSharing letName repr e)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr e)
-> ObserveSharing letName repr e
forall a b. (a -> b) -> a -> b
$
    Derived (ObserveSharing letName repr) a
-> Derived (ObserveSharing letName repr) b
-> Derived (ObserveSharing letName repr) c
-> Derived (ObserveSharing letName repr) d
-> Derived (ObserveSharing letName repr) e
FinalizeSharing letName repr a
-> FinalizeSharing letName repr b
-> FinalizeSharing letName repr c
-> FinalizeSharing letName repr d
-> FinalizeSharing letName repr e
f (FinalizeSharing letName repr a
 -> FinalizeSharing letName repr b
 -> FinalizeSharing letName repr c
 -> FinalizeSharing letName repr d
 -> FinalizeSharing letName repr e)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b
      -> FinalizeSharing letName repr c
      -> FinalizeSharing letName repr d
      -> FinalizeSharing letName repr e)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr a
a
      ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr b
   -> FinalizeSharing letName repr c
   -> FinalizeSharing letName repr d
   -> FinalizeSharing letName repr e)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c
      -> FinalizeSharing letName repr d
      -> FinalizeSharing letName repr e)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> ObserveSharing letName repr b
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr b)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr b
b
      ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr c
   -> FinalizeSharing letName repr d
   -> FinalizeSharing letName repr e)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr d -> FinalizeSharing letName repr e)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> ObserveSharing letName repr c
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr c)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr c
c
      ReaderT
  (HashSet SharingName)
  (State (ObserveSharingState letName))
  (FinalizeSharing letName repr d -> FinalizeSharing letName repr e)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr d)
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr e)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> ObserveSharing letName repr d
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr d)
forall letName (repr :: * -> *) a.
ObserveSharing letName repr a
-> ReaderT
     (HashSet SharingName)
     (State (ObserveSharingState letName))
     (FinalizeSharing letName repr a)
unObserveSharing ObserveSharing letName repr d
d
instance Referenceable letName (ObserveSharing letName repr) where
  ref :: Bool -> letName -> ObserveSharing letName repr a
ref = [Char] -> Bool -> letName -> ObserveSharing letName repr a
forall a. HasCallStack => [Char] -> a
error [Char]
"[BUG]: observeSharing MUST NOT be applied twice"
instance Definable letName (ObserveSharing letName repr) where
  def :: letName
-> ObserveSharing letName repr a -> ObserveSharing letName repr a
def = [Char]
-> letName
-> ObserveSharing letName repr a
-> ObserveSharing letName repr a
forall a. HasCallStack => [Char] -> a
error [Char]
"[BUG]: observeSharing MUST NOT be applied twice"
instance Letsable letName (ObserveSharing letName repr) where
  lets :: LetBindings letName (ObserveSharing letName repr)
-> ObserveSharing letName repr a -> ObserveSharing letName repr a
lets = [Char]
-> LetBindings letName (ObserveSharing letName repr)
-> ObserveSharing letName repr a
-> ObserveSharing letName repr a
forall a. HasCallStack => [Char] -> a
error [Char]
"[BUG]: observeSharing MUST NOT be applied twice"

-- * Type 'FinalizeSharing'
-- | Remove 'def' when non-recursive or unused
-- or replace it by 'ref', moving 'def's to the top.
newtype FinalizeSharing letName repr a = FinalizeSharing { FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing ::
  MT.ReaderT (HS.HashSet letName)
    (MT.Writer (LetBindings letName repr))
      (repr a) }

type instance Derived (FinalizeSharing _letName repr) = repr
instance (Eq letName, Hashable letName) =>
  LiftDerived (FinalizeSharing letName repr) where
  liftDerived :: Derived (FinalizeSharing letName repr) a
-> FinalizeSharing letName repr a
liftDerived = ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
FinalizeSharing (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
 -> FinalizeSharing letName repr a)
-> (repr a
    -> ReaderT
         (HashSet letName) (Writer (LetBindings letName repr)) (repr a))
-> repr a
-> FinalizeSharing letName repr a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall (f :: * -> *) a. Applicative f => a -> f a
pure
instance (Eq letName, Hashable letName) =>
  LiftDerived1 (FinalizeSharing letName repr) where
  liftDerived1 :: (Derived (FinalizeSharing letName repr) a
 -> Derived (FinalizeSharing letName repr) b)
-> FinalizeSharing letName repr a -> FinalizeSharing letName repr b
liftDerived1 Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
f FinalizeSharing letName repr a
a = ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
-> FinalizeSharing letName repr b
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
FinalizeSharing (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
 -> FinalizeSharing letName repr b)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
-> FinalizeSharing letName repr b
forall a b. (a -> b) -> a -> b
$ repr a -> repr b
Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
f (repr a -> repr b)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
a
instance (Eq letName, Hashable letName) =>
  LiftDerived2 (FinalizeSharing letName repr) where
  liftDerived2 :: (Derived (FinalizeSharing letName repr) a
 -> Derived (FinalizeSharing letName repr) b
 -> Derived (FinalizeSharing letName repr) c)
-> FinalizeSharing letName repr a
-> FinalizeSharing letName repr b
-> FinalizeSharing letName repr c
liftDerived2 Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
-> Derived (FinalizeSharing letName repr) c
f FinalizeSharing letName repr a
a FinalizeSharing letName repr b
b = ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
-> FinalizeSharing letName repr c
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
FinalizeSharing (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
 -> FinalizeSharing letName repr c)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
-> FinalizeSharing letName repr c
forall a b. (a -> b) -> a -> b
$
    repr a -> repr b -> repr c
Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
-> Derived (FinalizeSharing letName repr) c
f (repr a -> repr b -> repr c)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> ReaderT
     (HashSet letName)
     (Writer (LetBindings letName repr))
     (repr b -> repr c)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
a
      ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (repr b -> repr c)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> FinalizeSharing letName repr b
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr b
b
instance (Eq letName, Hashable letName) =>
  LiftDerived3 (FinalizeSharing letName repr) where
  liftDerived3 :: (Derived (FinalizeSharing letName repr) a
 -> Derived (FinalizeSharing letName repr) b
 -> Derived (FinalizeSharing letName repr) c
 -> Derived (FinalizeSharing letName repr) d)
-> FinalizeSharing letName repr a
-> FinalizeSharing letName repr b
-> FinalizeSharing letName repr c
-> FinalizeSharing letName repr d
liftDerived3 Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
-> Derived (FinalizeSharing letName repr) c
-> Derived (FinalizeSharing letName repr) d
f FinalizeSharing letName repr a
a FinalizeSharing letName repr b
b FinalizeSharing letName repr c
c = ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr d)
-> FinalizeSharing letName repr d
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
FinalizeSharing (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr d)
 -> FinalizeSharing letName repr d)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr d)
-> FinalizeSharing letName repr d
forall a b. (a -> b) -> a -> b
$
    repr a -> repr b -> repr c -> repr d
Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
-> Derived (FinalizeSharing letName repr) c
-> Derived (FinalizeSharing letName repr) d
f (repr a -> repr b -> repr c -> repr d)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> ReaderT
     (HashSet letName)
     (Writer (LetBindings letName repr))
     (repr b -> repr c -> repr d)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
a
      ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (repr b -> repr c -> repr d)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
-> ReaderT
     (HashSet letName)
     (Writer (LetBindings letName repr))
     (repr c -> repr d)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> FinalizeSharing letName repr b
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr b
b
      ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (repr c -> repr d)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr d)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> FinalizeSharing letName repr c
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr c
c
instance (Eq letName, Hashable letName) =>
  LiftDerived4 (FinalizeSharing letName repr) where
  liftDerived4 :: (Derived (FinalizeSharing letName repr) a
 -> Derived (FinalizeSharing letName repr) b
 -> Derived (FinalizeSharing letName repr) c
 -> Derived (FinalizeSharing letName repr) d
 -> Derived (FinalizeSharing letName repr) e)
-> FinalizeSharing letName repr a
-> FinalizeSharing letName repr b
-> FinalizeSharing letName repr c
-> FinalizeSharing letName repr d
-> FinalizeSharing letName repr e
liftDerived4 Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
-> Derived (FinalizeSharing letName repr) c
-> Derived (FinalizeSharing letName repr) d
-> Derived (FinalizeSharing letName repr) e
f FinalizeSharing letName repr a
a FinalizeSharing letName repr b
b FinalizeSharing letName repr c
c FinalizeSharing letName repr d
d = ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr e)
-> FinalizeSharing letName repr e
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
FinalizeSharing (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr e)
 -> FinalizeSharing letName repr e)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr e)
-> FinalizeSharing letName repr e
forall a b. (a -> b) -> a -> b
$
    repr a -> repr b -> repr c -> repr d -> repr e
Derived (FinalizeSharing letName repr) a
-> Derived (FinalizeSharing letName repr) b
-> Derived (FinalizeSharing letName repr) c
-> Derived (FinalizeSharing letName repr) d
-> Derived (FinalizeSharing letName repr) e
f (repr a -> repr b -> repr c -> repr d -> repr e)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> ReaderT
     (HashSet letName)
     (Writer (LetBindings letName repr))
     (repr b -> repr c -> repr d -> repr e)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
a
      ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (repr b -> repr c -> repr d -> repr e)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
-> ReaderT
     (HashSet letName)
     (Writer (LetBindings letName repr))
     (repr c -> repr d -> repr e)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> FinalizeSharing letName repr b
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr b)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr b
b
      ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (repr c -> repr d -> repr e)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
-> ReaderT
     (HashSet letName)
     (Writer (LetBindings letName repr))
     (repr d -> repr e)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> FinalizeSharing letName repr c
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr c)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr c
c
      ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (repr d -> repr e)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr d)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr e)
forall (f :: * -> *) a b. Applicative f => f (a -> b) -> f a -> f b
<*> FinalizeSharing letName repr d
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr d)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr d
d
instance
  ( Referenceable letName repr
  , Eq letName
  , Hashable letName
  , Show letName
  ) => Referenceable letName (FinalizeSharing letName repr) where
  ref :: Bool -> letName -> FinalizeSharing letName repr a
ref Bool
isRec = repr a -> FinalizeSharing letName repr a
forall (repr :: * -> *) a.
LiftDerived repr =>
Derived repr a -> repr a
liftDerived (repr a -> FinalizeSharing letName repr a)
-> (letName -> repr a) -> letName -> FinalizeSharing letName repr a
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Bool -> letName -> repr a
forall letName (repr :: * -> *) a.
Referenceable letName repr =>
Bool -> letName -> repr a
ref Bool
isRec
instance
  ( Referenceable letName repr
  , Eq letName
  , Hashable letName
  , Show letName
  ) => Definable letName (FinalizeSharing letName repr) where
  def :: letName
-> FinalizeSharing letName repr a -> FinalizeSharing letName repr a
def letName
name FinalizeSharing letName repr a
body = ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
forall letName (repr :: * -> *) a.
ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
FinalizeSharing (ReaderT
   (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
 -> FinalizeSharing letName repr a)
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> FinalizeSharing letName repr a
forall a b. (a -> b) -> a -> b
$ do
    HashSet letName
refs <- ReaderT
  (HashSet letName)
  (Writer (LetBindings letName repr))
  (HashSet letName)
forall (m :: * -> *) r. Monad m => ReaderT r m r
MT.ask
    let (repr a
repr, LetBindings letName repr
defs) =
          Writer (LetBindings letName repr) (repr a)
-> (repr a, LetBindings letName repr)
forall w a. Writer w a -> (a, w)
MT.runWriter (Writer (LetBindings letName repr) (repr a)
 -> (repr a, LetBindings letName repr))
-> Writer (LetBindings letName repr) (repr a)
-> (repr a, LetBindings letName repr)
forall a b. (a -> b) -> a -> b
$ ReaderT
  (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
-> HashSet letName -> Writer (LetBindings letName repr) (repr a)
forall r (m :: * -> *) a. ReaderT r m a -> r -> m a
MT.runReaderT (FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
body) HashSet letName
refs
    if letName
name letName -> HashSet letName -> Bool
forall a. (Eq a, Hashable a) => a -> HashSet a -> Bool
`HS.member` HashSet letName
refs
      then do
        -- This 'def' is 'ref'erenced: move it into the result,
        -- to put it in scope even when some 'ref' to it exists outside of 'body'
        -- (which can happen when a body-expression is shared),
        -- and replace it by a 'ref'.
        WriterT (LetBindings letName repr) Identity ()
-> ReaderT (HashSet letName) (Writer (LetBindings letName repr)) ()
forall (t :: (* -> *) -> * -> *) (m :: * -> *) a.
(MonadTrans t, Monad m) =>
m a -> t m a
MT.lift (WriterT (LetBindings letName repr) Identity ()
 -> ReaderT
      (HashSet letName) (Writer (LetBindings letName repr)) ())
-> WriterT (LetBindings letName repr) Identity ()
-> ReaderT (HashSet letName) (Writer (LetBindings letName repr)) ()
forall a b. (a -> b) -> a -> b
$ LetBindings letName repr
-> WriterT (LetBindings letName repr) Identity ()
forall (m :: * -> *) w. Monad m => w -> WriterT w m ()
MT.tell (LetBindings letName repr
 -> WriterT (LetBindings letName repr) Identity ())
-> LetBindings letName repr
-> WriterT (LetBindings letName repr) Identity ()
forall a b. (a -> b) -> a -> b
$ letName
-> SomeLet repr
-> LetBindings letName repr
-> LetBindings letName repr
forall k v.
(Eq k, Hashable k) =>
k -> v -> HashMap k v -> HashMap k v
HM.insert letName
name (repr a -> SomeLet repr
forall (repr :: * -> *) a. repr a -> SomeLet repr
SomeLet repr a
repr) LetBindings letName repr
defs
        repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall (m :: * -> *) a. Monad m => a -> m a
return (repr a
 -> ReaderT
      (HashSet letName) (Writer (LetBindings letName repr)) (repr a))
-> repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall a b. (a -> b) -> a -> b
$ Bool -> letName -> repr a
forall letName (repr :: * -> *) a.
Referenceable letName repr =>
Bool -> letName -> repr a
ref Bool
False letName
name
      else
        -- Remove this unreferenced 'def' node.
        FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
forall letName (repr :: * -> *) a.
FinalizeSharing letName repr a
-> ReaderT
     (HashSet letName) (Writer (LetBindings letName repr)) (repr a)
unFinalizeSharing FinalizeSharing letName repr a
body

-- ** Class 'Letsable'
class Letsable letName repr where
  -- | @('lets' defs x)@ let-binds @(defs)@ in @(x)@.
  lets :: LetBindings letName repr -> repr a -> repr a
  lets LetBindings letName repr
defs = (Derived repr a -> Derived repr a) -> repr a -> repr a
forall (repr :: * -> *) a b.
LiftDerived1 repr =>
(Derived repr a -> Derived repr b) -> repr a -> repr b
liftDerived1 (LetBindings letName (Derived repr)
-> Derived repr a -> Derived repr a
forall letName (repr :: * -> *) a.
Letsable letName repr =>
LetBindings letName repr -> repr a -> repr a
lets ((\(SomeLet repr a
val) -> Derived repr a -> SomeLet (Derived repr)
forall (repr :: * -> *) a. repr a -> SomeLet repr
SomeLet (repr a -> Derived repr a
forall (repr :: * -> *) a.
Derivable repr =>
repr a -> Derived repr a
derive repr a
val)) (SomeLet repr -> SomeLet (Derived repr))
-> LetBindings letName repr -> LetBindings letName (Derived repr)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> LetBindings letName repr
defs))
  default lets ::
    Derivable repr =>
    FromDerived1 (Letsable letName) repr =>
    LetBindings letName repr -> repr a -> repr a

-- *** Type 'SomeLet'
data SomeLet repr = forall a. SomeLet (repr a)

-- *** Type 'LetBindings'
type LetBindings letName repr = HM.HashMap letName (SomeLet repr)

{-
-- | Not used but can be written nonetheless.
instance
  ( Letsable letName repr
  , Eq letName
  , Hashable letName
  , Show letName
  ) => Letsable letName (FinalizeSharing letName repr) where
  lets defs x = FinalizeSharing $ do
    ds <- traverse (\(SomeLet v) -> do
      r <- unFinalizeSharing v
      return (SomeLet r)
      ) defs
    MT.lift $ MT.tell ds
    unFinalizeSharing x
-}

-- *** Type 'OpenRecs'
-- | Mutually recursive terms, in open recursion style.
type OpenRecs letName a = LetRecs letName (OpenRec letName a)
-- | Mutually recursive term, in open recursion style.
-- The term is given a @final@ (aka. @self@) map
-- of other terms it can refer to (including itself).
type OpenRec letName a = LetRecs letName a -> a
-- | Recursive let bindings.
type LetRecs letName = HM.HashMap letName

-- | Least fixpoint combinator.
fix :: (a -> a) -> a
fix :: (a -> a) -> a
fix a -> a
f = a
final where final :: a
final = a -> a
f a
final

-- | Lest fixpoint combinator of mutually recursive terms.
-- @('mutualFix' opens)@ takes a container of terms
-- in the open recursion style @(opens)@,
-- and return that container of terms with their knots tied-up.
--
-- Used to express mutual recursion and to transparently introduce memoization,
-- between observed sharing ('defLet', 'call', 'jump')
-- and also between join points ('defJoin', 'refJoin').
--
-- Here all mutually dependent functions are restricted to the same polymorphic type @(a)@.
-- See http://okmij.org/ftp/Computation/fixed-point-combinators.html#Poly-variadic
mutualFix :: forall recs a. Functor recs => recs ({-finals-}recs a -> a) -> recs a
mutualFix :: recs (recs a -> a) -> recs a
mutualFix recs (recs a -> a)
opens = (recs a -> recs a) -> recs a
forall a. (a -> a) -> a
fix recs a -> recs a
f
  where
  f :: recs a -> recs a
  f :: recs a -> recs a
f recs a
recs = ((recs a -> a) -> recs a -> a
forall a b. (a -> b) -> a -> b
$ recs a
recs) ((recs a -> a) -> a) -> recs (recs a -> a) -> recs a
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> recs (recs a -> a)
opens