Why?

You have a program that has been working fine for 8 months. It breaks the problem up in small pieces, and it uses a simple solution for all the pieces. From the description you are giving, about the only thing that's against it is reading in a file twice, and some streamlining could have been programmed in. But overall, you have a pretty good program, and it works.

But now you have an urge to rewrite it. And what my impression is, in a more complex way. I'd say, don't do it.

I think I am that point but what criteria do I use to determine whether I should stop using plain regexes and consider using Parse::RecDescent?
Never. If you can do it with plain regexes, do it with plain regexes. Regexes can backtrack, but Parse::RecDescent will backtrack much more, unless you put a lot of work in it. Parse::RecDescent is slow. You'd only use Parse::RecDescent if your problem can't be solved with plain regexes. And even then you might want to consider regexes with advanced features over Parse::RecDescent. I can't prove it (yet), but I think that anything that can be parsed with a Parse::RecDescent parser, can be parsed with a regex (except perhaps cases where you modify the parser mid-parse).

Abigail

In reply to Re: To parse or not to parse by Abigail-II
in thread To parse or not to parse by set_uk

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