I'd be verbose. It's an uncommon operation, bound to surprise a readera bit.It's better to type a few more letters.
See update.
I did not try to compile it, but what happens if the enum elementshave the same name ? The same min/max/values ? Like this: enum E1 { a, b, c } alias E111 = join!(E1, E1, E1);
This should give a better error message, than current mixin error. I'll work on that.
I would put it in std.typecons, since it's a type constructor
Ok. Thx!