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0 pointstough10mo ago0 comments

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That doesn’t answer the question. By “validate”, I mean “prove to yourself that the regular expression is correct”. Much like with program code, you can’t do that by only testing it. You need to understand what the expression actually says.

widdershins10mo ago

Testing something is the best way to prove that it behaves correctly in all the cases you can think of. Relying on your own (fallible) understanding is dangerous.

Of course, there may be cases you didn't think of where it behaves incorrectly. But if that's true, you're just as likely to forget those cases when studying the expression to see "what it actually says". If you have tests, fixing a broken case (once you discover it) is easy to do without breaking the existing cases you care about.

So for me, getting an AI to write a regex, and writing some tests for it (possibly with AI help) is a reasonable way to work.

layer810mo ago

I don’t believe this is true. That’s why we do mathematical proofs, instead of only testing all the cases one can think of. It’s important to sanity-check one’s understanding with tests, but mere black-box testing is no substitute for the understanding.

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marcosdumay10mo ago

Notice that site has a very usable reference list you can consult for all those details the GP forgets.

j / k navigate · click thread line to collapse

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layer810mo ago

widdershins10mo ago

Testing something is the best way to prove that it behaves correctly in all the cases you can think of. Relying on your own (fallible) understanding is dangerous.

So for me, getting an AI to write a regex, and writing some tests for it (possibly with AI help) is a reasonable way to work.

layer810mo ago

1 more reply

marcosdumay10mo ago

Notice that site has a very usable reference list you can consult for all those details the GP forgets.

j / k navigate · click thread line to collapse