{-# RULES
"fold/build" forall k z (g :: forall b. (a -> b -> b) -> b -> b). foldr k z (build g) = g k z
    #-}

{-# RULES
"fold/build" forall
    k
    z
    ( g ::
        forall b.
        (a -> b -> b) ->
        b ->
        b
    ).
    foldr k z (build g) =
        g k z
    #-}
