2013-09-27 23:52:36 +00:00
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{- utilities for simple data types
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-
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2015-01-21 16:50:09 +00:00
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- Copyright 2013 Joey Hess <id@joeyh.name>
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2013-09-27 23:52:36 +00:00
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-
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2014-05-10 14:01:27 +00:00
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- License: BSD-2-clause
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2013-09-27 23:52:36 +00:00
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-}
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module Utility.Data where
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{- First item in the list that is not Nothing. -}
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firstJust :: Eq a => [Maybe a] -> Maybe a
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firstJust ms = case dropWhile (== Nothing) ms of
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[] -> Nothing
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(md:_) -> md
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eitherToMaybe :: Either a b -> Maybe b
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eitherToMaybe = either (const Nothing) Just
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