cryptonite/Crypto/Hash/Internal.hs
2014-07-07 14:55:55 +01:00

25 lines
651 B
Haskell

{-# LANGUAGE CPP #-}
-- |
-- Module : Crypto.Hash.Internal
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : experimental
-- Portability : unknown
module Crypto.Hash.Internal where
import System.IO.Unsafe
-- | perform io for hashes that do allocation and ffi.
-- unsafeDupablePerformIO is used when possible as the
-- computation is pure and the output is directly linked
-- to the input. we also do not modify anything after it has
-- been returned to the user.
unsafeDoIO :: IO a -> a
#if __GLASGOW_HASKELL__ > 704
unsafeDoIO = unsafeDupablePerformIO
#else
unsafeDoIO = unsafePerformIO
#endif