A built in method (it's not an identifier, btw) would be faster than any custom identifier. Obviously, the difference in speed would be negligible, but it would definitely not be slower. The main benefit is that it's an obvious way of obtaining whether or not something is even or odd.
Yes, the most common (I think) method right now is to use % to see... basically checking if the number can be evenly divided by 2. That's pretty easy to do and anyone with either a math background or who has scripted enough to know about it can do it. I still say having "isodd" or "iseven" would be good. Apparently, I'm outvoted on this, but it's up to Khaled in the end, so I'll still stand in favor of it and let him decide.
And, for those stating that it can be done using other methods that are easy, so shouldn't be added... why then do we bother having isop, etc?
if ($nick isop $chan) {}
if ($nick($chan,$nick,o)) {}
That's four characters difference and results would do the same thing. Obviously, isop is better, but the point is that there is an alternate method that doesn't even increase the amount of script by very much. With the iseven/isodd check, the difference in script size is a lot more. So considering adding it would make finding odd/even more intuitive and shouldn't be difficult to add, I don't think the reasoning that it's possible in other ways is really that valid. Again, that's just my opinion and I seem to be in the minority.
