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Regex Isn't Hard (2023)

(timkellogg.me)
75 points asicsp | 1 comments | | HN request time: 0.213s | source
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michaelt ◴[] No.43750496[source]
> e.g. This pattern ([0-9][0-9]?[0-9]][.])+ matches one, two or three digits followed by a . and also matches repeated patterns of this. This wold match an IP address (albeit not strictly).

I love regular expressions but one thing I've learned over the years is the syntax is dense enough that even people who are confident enough to start writing regex tutorials often can't write a regex that matches an IP address.

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1. stavros ◴[] No.43750641[source]
Well, it depends on how specific you want to be. You could do `.*`, and this will match an IP address, or you can be as specific as trying to specify number ranges digit by digit, which is so complicated that it doesn't merit a "can't even".

Also, `16843009` is an IP address, try pinging it.