src/Id.hs


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module Id
( newId,
  nextId
) where

{- 
 -
 - Écrit par Hédy GIRAUDEAU
 - 27/07/17
 -
-}

import Data.IORef
import Data.Functor

type Id_number a = IORef a

newId = (newIORef 0)
nextId cnt = modifyIORef cnt (+1) >> (+0) <$> readIORef cnt