{-# LANGUAGE Arrows #-}

foo x = proc a -> a -< x

foolr x = proc a -> x >- a

bar f x =
    proc
        ( y
            , z
            , w
            )
    ->
        f -- The value
            -<
                ( x -- Foo
                , w -- Bar
                , z -- Baz
                )

baz x = proc a -> a -<< x

bazlr x = proc a -> x >>- a