Re: More on RPG style

Hello,

Seriously, how is "If not something();" different from "If something() =
false;" or "If something() = '0';?" They all mean the same thing: not =
'0' = false. To me, it's a matter of preference. Since my logic spans
several languages, "if not" is common and not difficult to read. I
would rather have recognizable commonalities between code variances than
gear myself up for avoidable nuances.

Yeah, I agree with Tom with regards to the examples that have been posted here so far. In those examples, anyone should be able to figure it out quite easily.

However, at the same time, I also agree that negative logic makes things a little trickier to understand. Did it make any difference to the examples posted here so far? No. They were too simple! But, there is a point at which program logic starts to get too convoluted and hard to read. And negative logic can sometimes be the "last straw" in making something convoluted.

Consider this example:

chain ItemNo ItemMaster;
if not %found;
NotValid = *on;
endif;

. . . 100 lines of code . . .

If (not NotValid);
// use item
endif;

This, to me, is getting convoluted. The negatives in the "not notvalid" make things complex... but that's still a relatively simple example. Even so, it's nicer to have something like this:

chain ItemNo ItemMaster;
if not %found;
Valid = *on;
endif;

. . . 100 lines of code . . .

if Valid;
// use item
endif;

The more positives in your logic, the easier it is to understand. There are certainly cases where negative logic is easy and not a problem.. but it should be tempered with judgement. If it looks too complex, the logic should be cleaned up a bit.