-- | Add an extension onto the end of the target of a 'Lens' and return the result
--
-- >>> _1 <<.>~ "txt" $ ("hello","world")
-- ("hello.txt",("hello.txt","world"))
--
-- When you do not need the result of the operation, ('<.>~') is more flexible.
(<<.>~) :: LensLike ((,)FilePath) s a FilePath FilePath -> String -> s -> (FilePath, a)
l <<.>~ m = l <%~ (<.> m)
(<<.>~) :: LensLike ((,)FilePath) s a FilePath FilePath -> String -> s -> (FilePath, a)
l <<.>~ m = l <%~ (<.> m)
l <<.>~ m = l <%~ (<.> m)