--- prelude.pvs.orig 2021-05-19 17:01:04.955518648 +0200 +++ prelude.pvs 2021-05-19 17:01:15.191586114 +0200 @@ -1418,11 +1418,11 @@ image(f, X): set[R] = {y: R | (EXISTS (x:(X)): y = f(x))} - image(f)(X): set[R] = image(f, X) + image(f)(X): MACRO set[R] = image(f, X) inverse_image(f, Y): set[D] = {x: D | member(f(x), Y)} - inverse_image(f)(Y): set[D] = inverse_image(f, Y) + inverse_image(f)(Y): MACRO set[D] = inverse_image(f, Y) image_inverse_image: LEMMA subset?(image(f, inverse_image(f, Y)), Y)