If you don't see the relevance of the distinction between code generated at runtime (sometimes called "active code generation") and that generated earlier ("passive code generation"), I'm guessing you haven't worked on a large project that used passive code generation. The problem is that there will be an emergency fix and someone will edit one of the generated files because it's much easier than trying to understand and change the code generation code. And then you are in big trouble.

Anyway, both of you seem to be implying that I said something like "generating anything from anything else is always bad." That's not what I'm saying at all. Let me try to re-state it more clearly:

In most cases where you could use code generation to solve a problem, you could also use a data structure and some subs to solve it. To quote from the wiki link I posted, "Anything you can do by generating code, I can do by calling data driven subroutines." Using subs is better because it is easier to understand (no need to parse two-levels of code at once in your head) and avoids the danger of hand-editing.

I'm not claiming that there are no situations at all where code generation is required. A common reason to use active code generation is the performance gain you can sometimes get with it (e.g. templating systems often generate perl code from templates).

Even if you completely disagree, the wiki link I posted is pretty interesting reading, and makes good points on both sides.

In reply to Re^3: (OT) Generated Code vs. Libraries by perrin
in thread (OT) Generated Code vs. Libraries by Mutant

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