MutableReference.hs

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module Feldspar.Core.Frontend.MutableReference
where

import Language.Syntactic

import Feldspar.Core.Types
import Feldspar.Core.Constructs
import Feldspar.Core.Constructs.MutableReference
import Feldspar.Core.Frontend.Mutable

import Data.IORef

newtype Ref a = Ref { unRef :: Data (IORef (Internal a)) }

instance Syntax a => Syntactic (Ref a) FeldDomainAll
  where
    type Internal (Ref a) = IORef (Internal a)
    desugar = desugar . unRef
    sugar   = Ref . sugar

instance Syntax a => Syntax (Ref a)

newRef :: Syntax a => a -> M (Ref a)
newRef = sugarSym NewRef

getRef :: Syntax a => Ref a -> M a
getRef = sugarSym GetRef

setRef :: Syntax a => Ref a -> a -> M ()
setRef = sugarSym SetRef

modifyRef :: Syntax a => Ref a -> (a -> a) -> M ()
modifyRef r f = getRef r >>= setRef r . f