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authorJoey Hess2014-05-14 19:41:05 -0400
committerJoey Hess2014-05-14 19:41:05 -0400
commit7115d1ec162b4059b3e8e8f84bd8d5898c1db025 (patch)
tree42c1cce54e890e1d56484794ab33129132d8fee2 /src/Utility/Data.hs
parentffe371a9d42cded461236e972a24a142419d7fc4 (diff)
moved source code to src
This is to work around OSX's brain-damange regarding filename case insensitivity. Avoided moving config.hs, because it's a config file. Put in a symlink to make build work.
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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