"hidden" variants?

[René J.V. Bertin]

Hi,

Can a port have variants that it doesn't "advertise"? In other words, what happens if a portfile uses `variant_isset` to check whether or not a variant has been selected, but doesn't contain (or contains a commented-out) declaration for that variant?
Am I right that everything still works normally and that the variant can thus be installed if you know it exists? Or would that be purely by accident?

Context: the +exclusive variant of my co-installable qt4-mac port version. I'm quite confident by now that it is no longer required, but see no point in making it impossible to use just yet.

R.