propellor/Utility/Applicative.hs

17 lines
371 B
Haskell

{- applicative stuff
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Utility.Applicative where
{- Like <$> , but supports one level of currying.
-
- foo v = bar <$> action v == foo = bar <$$> action
-}
(<$$>) :: Functor f => (a -> b) -> (c -> f a) -> c -> f b
f <$$> v = fmap f . v
infixr 4 <$$>