8ea5f3ff99
Eliminated some dead code. In other cases, exported a currently unused function, since it was a logical part of the API. Of course this improves the API documentation. It may also sometimes let ghc optimize code better, since it can know a function is internal to a module. 364 modules still to go, according to git grep -E 'module [A-Za-z.]+ where'
22 lines
464 B
Haskell
22 lines
464 B
Haskell
{- utilities for simple data types
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-
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- Copyright 2013 Joey Hess <id@joeyh.name>
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-
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- License: BSD-2-clause
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-}
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{-# OPTIONS_GHC -fno-warn-tabs #-}
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module Utility.Data (
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firstJust,
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eitherToMaybe,
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) 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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