I didn’t know about this so I tried testing it out. Yes, this is possible, but requires enabling a specific flag (x when it comes to regexp2) assuming the engine even supports this feature.

Not much substance to their argument, mostly just whining. Funny website, though.

The term’s connection with racism, as well as the value in avoiding its use has been disputed.

https://en.wikipedia.org/wiki/Blacklist_(computing)#Controversy_over_terminology

(See the section that follows for more context.)

Those would be interesting features, but it currently only operates on plain text lists, or lists with wildcards (*) which are converted into regexp (.*), or lists with CIDR suffixes (127.0.0.0/24). You can disable escaping, but list2regexp doesn’t understand the individual segments of regular expressions, so the result will probably be wrong.

With that said, the library being used to handle escaping and testing the generated patterns (regexp2) does expose the syntax tree so the information is available to do interesting things with, such as what you suggest.

Being pretty or short is not a goal of this project, nor do I see the value in such goals.

In my case, to efficiently match against a large number of IP addresses and IP address ranges:

https://codeberg.org/tslocum/sriracha/src/commit/5bf24b0daabd058c2714427da17c7ea16b7cd43a/internal/server/server.go#L447

Here is an example. Given the following list of strings:

1.2.3.4
127.0.0.1
127.0.0.2
127.0.0.11
128.0.0.1
125.0.0.*
200.0.0.1
2001:0db8:85a3:0000:0000:8a2e:0370:1300
2001:0db8:85a3:0000:0000:8a2e:0370:1330
2001:0db8:85a3:0000:0000:8a2e:0370:1337
あいうえお
あいうえこ
😃😁😆😐
😃😁😆
😃😁🤣

list2regexp will return the following pattern:

^(?:1(?:(?:\.(?:2(?:\.(?:3(?:\.(?:4))))))|(?:2(?:(?:5(?:\.(?:0(?:\.(?:0(?:\.(?:.*)))))))|(?:7(?:\.(?:0(?:\.(?:0(?:\.(?:(?:1(?:|(?:1)))|(?:2))))))))|(?:8(?:\.(?:0(?:\.(?:0(?:\.(?:1)))))))))))|(?:2(?:0(?:0(?:(?:\.(?:0(?:\.(?:0(?:\.(?:1))))))|(?:1(?::(?:0(?:d(?:b(?:8(?::(?:8(?:5(?:a(?:3(?::(?:0(?:0(?:0(?:0(?::(?:0(?:0(?:0(?:0(?::(?:8(?:a(?:2(?:e(?::(?:0(?:3(?:7(?:0(?::(?:1(?:3(?:(?:0(?:0))|(?:3(?:(?:0|7))))))))))))))))))))))))))))))))))))))))))|(?:あ(?:い(?:う(?:え(?:(?:お|こ))))))|(?:😃(?:😁(?:(?:😆(?:|(?:😐)))|(?:🤣))))$