to have the advantage of two things, when usually doing or using one makes it impossible to have the other. This is an affirmative
form of the
phrase you can't have your
cake and
eat it too, literally meaning that if you
want to keep a
cake you cannot
eat it because if you
eat it you no longer have it. Used figuratively it means you cannot
use or spend something and then still expect to have it. The
origin of this
phrase is unknown; however, it has been in
use at least since the 1500s.