Nitorami,
Sorry. I evidently didn't understand your post first time I read.
I do have concerns with "+". I think that everyone that uses Free Pascal for math will have concerns.
In my case, it won't brake any code although I'm looking for another symbol in the keyboard that could be used for concat. What about & for concatenation?
BTW, is this concatenation or union? If it is union, I might suggest || instead.