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{-# LANGUAGE Safe #-}
{-# LANGUAGE CPP #-}
-- This module deliberately declares orphan instances:
{-# OPTIONS_GHC -fno-warn-orphans #-}
-----------------------------------------------------------------------------
-- |
-- Module : Text.Show.Functions
-- Copyright : (c) The University of Glasgow 2001
-- License : BSD-style (see the file libraries/base/LICENSE)
--
-- Maintainer : libraries@haskell.org
-- Stability : provisional
-- Portability : portable
--
-- Optional instance of 'Text.Show.Show' for functions:
--
-- > instance Show (a -> b) where
-- > showsPrec _ _ = showString \"\<function\>\"
--
-----------------------------------------------------------------------------
module Text.Show.Functions () where
import Prelude
#ifndef __NHC__
instance Show (a -> b) where
showsPrec _ _ = showString "<function>"
#else
instance (Show a,Show b) => Show (a->b) where
showsPrec d a = showString "<<function>>"
showsType a = showChar '(' . showsType value . showString " -> " .
showsType result . showChar ')'
where (value,result) = getTypes undefined
getTypes x = (x,a x)
#endif
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