File: Data.hs

package info (click to toggle)
git-annex 10.20230126-3
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 69,344 kB
  • sloc: haskell: 74,654; javascript: 9,103; sh: 1,304; makefile: 203; perl: 136; ansic: 44
file content (38 lines) | stat: -rw-r--r-- 693 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
{- 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