-- | Modify the target(s) of a 'Lens'', 'Iso'', 'Setter'' or 'Traversal'' by adding an extension.
--
-- >>> execState (both <.>= "txt") ("hello","world")
-- ("hello.txt","world.txt")
--
-- @
-- ('<.>=') :: 'MonadState' s m => 'Setter'' s 'FilePath' -> 'String' -> m ()
-- ('<.>=') :: 'MonadState' s m => 'Iso'' s 'FilePath' -> 'String' -> m ()
-- ('<.>=') :: 'MonadState' s m => 'Lens'' s 'FilePath' -> 'String' -> m ()
-- ('<.>=') :: 'MonadState' s m => 'Traversal'' s 'FilePath' -> 'String' -> m ()
-- @
(<.>=) :: MonadState s m => ASetter' s FilePath -> String -> m ()
l <.>= b = State.modify (l <.>~ b)
(<.>=) :: MonadState s m => ASetter' s FilePath -> String -> m ()
l <.>= b = State.modify (l <.>~ b)
l <.>= b = State.modify (l <.>~ b)