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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 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