Document regex capabilities

[kubouch]

Related problem

Asked here
#4266

Describe the solution you'd like

We should state what kind of regex we support.

This might be as simple as stating we use the regex crate. I haven't looked at all the commands that use regex, so I'm not sure.

Describe alternatives you've considered

No response

Additional context and details

No response

[fdncred]

agreed. i've chased this question myself a couple times. having it documented would help because it is a very particular flavor of regex.

[sakimyto]

Hi, I was just trying to read the whole project before I joined the development.
Let me see if I understood it right.
For creating documentation on regex, check where regex is used in the entire nushell/crates/ directory, is that it?

[kubouch]

@sakimyto Yeah, that sounds right.

We're about to merge the big update relatively soon, but I don't think it will impact this issue since AFAIK we did not change anything regarding regex.

[sakimyto]

@kubouch
OK. Let's find out where it is used.

[sakimyto]

First, I checked each of their Cargo.toml. But the only thing I could find related to regular expressions was rust_lang/regex. However, I found a possibility that it uses other crates in dependencies of dependencies. For exmaple, nu_plugin_textview -> sharkdp/bat -> rust-onig/rust-onig.
We should also look into crates for dependents, right?

[fdncred]

textview will be removed in the next version of nushell but regex is used in a few place like in the str find-replace command. so, I'd just focus on the https://github.com/rust-lang/regex

[sakimyto]

Then, I'll add that we basically use rust-lang/regex to the docs and contributor book？

[kubouch]

@sakimyto Yeah, that sounds good!

[sakimyto]

Hmm, where would be a good place to write this?
I'm thinking of adding to 2 parts.

1. Add to the end of https://github.com/nushell/nushell.github.io/blob/master/contributor-book/plugins.md#creating-a-plugin-in-rust
2. Add to the end of https://github.com/nushell/nushell/blob/main/docs/commands/README.md#anything-else

[fdncred]

Maybe make a new section in the book called regex?

[sakimyto]

@fdncred I'm grateful for your support. Created PR.
nushell/nushell.github.io#218

[kubouch]

Fixed with @sakimyto 's PR