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Parser Combinators Beat Regexes

(entropicthoughts.com)
120 points mooreds | 1 comments | 09 Apr 25 21:53 UTC | HN request time: 0.201s | source
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arn3n ◴[10 Apr 25 00:34 UTC] No.43639465[source]▶
“In other languages, it would be considered overkill to write a full parser when a simple regex can do the same thing. In Haskell, writing a parser is no big deal. We just do it and move on with our lives.”

I see a long code file filled with comments and long paragraph-level explanations. I think I’d rather just learn and use regex.

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1. codebje ◴[10 Apr 25 01:58 UTC] No.43639912[source]▶
The main advantage of recursive descent parsing is readability. Forget the machinery of the parser, which is (a) trivial enough that AI will generate correctly it for you with next to no prompting, and (b) widely available in libraries anyway. The win is writing a parser that reads like the grammar it implements, which means changes to your grammar are easy to apply to your parser.

Regexes are effectively write-only. If you change the grammar parsed by a regex, you're probably going to discard the regex and make a new one.