Ah, I think now I get it. You want to specify the name of the output file using a conditional statement. Unfortunately, it's not possible. The first line with switches is logically being a part of the command line and not TeX instruction stream. Once TeX engine starts it's job of grinding through the typesetting instructions it's to late to specify job name. But as you say, it's not a big deal to comment/uncomment a line or two of code.
Cheers,
Tomek
General ⇒ Changing the output file name
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