File: Data.hs

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{- utilities for simple data types
 -
 - Copyright 2013 Joey Hess <id@joeyh.name>
 -
 - License: BSD-2-clause
 -}

{-# OPTIONS_GHC -fno-warn-tabs #-}

module Utility.Data (
	firstJust,
	eitherToMaybe,
) where

{- 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