27 lines
574 B
Haskell
27 lines
574 B
Haskell
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{- monadic conditional operators
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-
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- Copyright 2011 Joey Hess <joey@kitenet.net>
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-
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- Licensed under the GNU GPL version 3 or higher.
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-}
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module Utility.Conditional where
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import Control.Monad (when, unless)
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whenM :: Monad m => m Bool -> m () -> m ()
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whenM c a = c >>= flip when a
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unlessM :: Monad m => m Bool -> m () -> m ()
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unlessM c a = c >>= flip unless a
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(>>?) :: Monad m => m Bool -> m () -> m ()
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(>>?) = whenM
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(>>!) :: Monad m => m Bool -> m () -> m ()
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(>>!) = unlessM
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-- low fixity allows eg, foo bar >>! error $ "failed " ++ meep
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infixr 0 >>?
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infixr 0 >>!
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