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authorJoey Hess2014-05-14 19:47:17 -0400
committerJoey Hess2014-05-14 19:47:17 -0400
commit39217c55690de5641a9fe4ef2236d6127ebbcbb3 (patch)
tree31284fd462e2d02cf9bf0b8077c0e8dd34181988 /src/Utility/Data.hs
parenteb6e6fe11290971b37a18d9a78f6d9b78228c06f (diff)
parent7115d1ec162b4059b3e8e8f84bd8d5898c1db025 (diff)
Merge branch 'joeyconfig'
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+{- utilities for simple data types
+ -
+ - Copyright 2013 Joey Hess <joey@kitenet.net>
+ -
+ - License: BSD-2-clause
+ -}
+
+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