Fun with (.).(.)

Owl.hs

module Owl where

import System.FilePath ((</>))

fromMaybe :: a -> Maybe a -> a
fromMaybe a m = case m of
    Nothing -> a
    Just b  -> b

prependPath :: FilePath -> FilePath -> FilePath
prependPath dir base = dir </> base

makePath'', makePath', makePath :: FilePath -> FilePath -> Maybe FilePath -> FilePath

makePath'' dir def maybeValue = prependPath dir $ fromMaybe def maybeValue

makePath'  dir def = prependPath dir . fromMaybe def

(.:) :: (b -> c) -> (d -> a -> b) -> d -> a -> c
(.:) = (.) . (.)

makePath base = prependPath base .: fromMaybe