    {-# LANGUAGE CPP #-}

    #if MIN_VERSION_base(4,4,0)
    {-# OPTIONS_GHC -fno-warn-orphans #-}
    #endif
    {-|
    Module:      TextShow.GHC.Fingerprint
    Copyright:   (C) 2014-2017 Ryan Scott
    License:     BSD-style (see the file LICENSE)
    Maintainer:  Ryan Scott
    Stability:   Provisional
    Portability: GHC

    'TextShow' instance for 'Fingerprint'.
    Only provided if using @base-4.4.0.0@ or later.

    /Since: 2/
    -}
    module TextShow.GHC.Fingerprint () where

    #if MIN_VERSION_base(4,4,0)
    import Data.Monoid.Compat ((<>))
    import Data.Semigroup (mtimesDefault)
    import Data.Text.Lazy.Builder (Builder, singleton)
    import Data.Word (Word64)

    import GHC.Fingerprint.Type (Fingerprint(..))

    import TextShow.Classes (TextShow(..))
    import TextShow.Data.Integral (showbHex)
    import TextShow.Utils (lengthB)

    -- | /Since: 2/
    instance TextShow Fingerprint where
        showb (Fingerprint w1 w2) = hex16 w1 <> hex16 w2
          where
            hex16 :: Word64 -> Builder
            hex16 i = let hex = showbHex i
                      in mtimesDefault (max 0 $ 16 - lengthB hex) (singleton '0') <> hex
    #endif