    {-# OPTIONS_GHC -Wunused-imports #-}

    -- | Utilities for Data.IORef.

    module Agda.Utils.IORef
      ( module Data.IORef
      , module Agda.Utils.IORef
      ) where

    import Data.IORef

    -- | Read 'IORef', modify it strictly, and return old value.
    readModifyIORef' :: IORef a -> (a -> a) -> IO a
    readModifyIORef' :: forall a. IORef a -> (a -> a) -> IO a
    readModifyIORef' IORef a
    ref a -> a
    f = do
        x <- IORef a -> IO a
    forall a. IORef a -> IO a
    readIORef IORef a
    ref
        writeIORef ref $! f x
        return x