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{- utilities for simple data types
-
- Copyright 2013-2021 Joey Hess <id@joeyh.name>
-
- License: BSD-2-clause
-}
{-# OPTIONS_GHC -fno-warn-tabs #-}
module Utility.Data (
firstJust,
eitherToMaybe,
s2w8,
w82s,
) where
import Data.Word
{- First item in the list that is not Nothing. -}
firstJust :: Eq a => [Maybe a] -> Maybe a
firstJust ms = case dropWhile (== Nothing) ms of
[] -> Nothing
(md:_) -> md
eitherToMaybe :: Either a b -> Maybe b
eitherToMaybe = either (const Nothing) Just
c2w8 :: Char -> Word8
c2w8 = fromIntegral . fromEnum
w82c :: Word8 -> Char
w82c = toEnum . fromIntegral
s2w8 :: String -> [Word8]
s2w8 = map c2w8
w82s :: [Word8] -> String
w82s = map w82c
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