[Language Addition] Regular Expressions

[RokeJulianLockhart]

Language name

IEEE Std 1003.1-2024 Extended Regular Expressions

URL of example repository

github.com/AnFunctionArray/cperllexer/blob/1c4f989108d7b580d8de467a4b0917482be3afd7/inner.regex ¹

URL of syntax highlighting grammar

1. slevithan/regex-colorizer/blob/4f6552279edde31ae9480cabf9984953165edd64/src/index.js

2. gist.github.com/aifrak/36d54bf8c97b9b888e7dc41ee00547be

3. github.com/xavierog/codemirror-mode-pcre/blob/5178ef29b1b2bdf8c38a32ecc116efea44399b62/src/pcre.js ²

4. github.com/googlearchive/code-prettify/blob/453bd5f51e61245339b738b1bbdd42d7848722ba/src/prettify.js ³

5. PrismJS/prism/blob/b6a6687674bdac60fac596e16558217344176ed6/src/languages/regex.js ⁴

Most popular extensions

.RegEx would the applicable extension, because none have been standardised.

Detected language

Currently, text/plain.

Footnotes

1. github.com/search?q=path%3A*.regex&type=code ↩

2. discuss.codemirror.net/t/6217/2 ↩

3. meta.stackoverflow.com/revisions/374389/3;) ↩

4. forum.obsidian.md/t/90378/3 ↩

[Alhadis]

The site already supports regular expressions, and it recognises both the .regexp and .regex file-extensions. Also, the inner.regex file you linked to is being highlighted perfectly fine. What's missing, exactly?

Detected language: Currently, text/plain.

Where exactly are you seeing this?

[RokeJulianLockhart]

The inner.regex file you linked to is being highlighted perfectly fine. What's missing, exactly?

@Alhadis, I had expected highlighting that was more specific, like what gist.github.com/aifrak/36d54bf8c97b9b888e7dc41ee00547be/451c2b2ed3c96e09cc7ae3a420559b628d51cccb#before-dark-modern-vscode-theme depicts: ¹

Before (Dark Modern VSCode theme)

After (Dark Modern VSCode theme)

Consequently, I'd presumed that those files were being highlighted with another language which, coincidentally, managed to highlight enough of it that it merely appeared syntax-highlighted.

If, instead, the grammar is merely somewhat basic, that's sufficient, because the undermentioned lack of grammar in specific situations is the original reason that I noticed this:

Detected language

Currently, text/plain.

Where exactly are you seeing this?

Inside CommonMark syntax-highlight-enabled <pre><code>s (~~~RegEx): ²

[^1]: ~~~RegEx
    "(?:(?:headers)|(?:cookies))"\s*:\s*(?:\{[^{}]*\}|\[[^\[\]]*\]|"[^"]*"|[^,}\]]*)(?:,)?\s*
    
    ~~~

I know that this is invalid, because it reproduces github/markup/issues/1851 if I surround it with blockquotes.

Footnotes

1. gist.githubusercontent.com/aifrak/36d54bf8c97b9b888e7dc41ee00547be/raw/451c2b2ed3c96e09cc7ae3a420559b628d51cccb/syntax-highlighting-for-regex-vscode.md ↩

2. https://github.com/hmrc/hmrc-frontend/issues/495#issue-3519417479:~:text=Footnotes ↩

[lildude]

Inside CommonMark syntax-highlight-enabled <pre><code>s (~~~RegEx): 2

I'm not sure what you're pointing out… this works fine…

• using ~~~RegEx

(?:(?:headers)|(?:cookies))"\s*:\s*(?:\{[^{}]*\}|\[[^\[\]]*\]|"[^"]*"|[^,}\]]*)(?:,)?\s*

• and ```RegEx

(?:(?:headers)|(?:cookies))"\s*:\s*(?:\{[^{}]*\}|\[[^\[\]]*\]|"[^"]*"|[^,}\]]*)(?:,)?\s*

[RokeJulianLockhart]

@lildude, you're not utilising it inside a footnote:

[^1]

[^1]: ~~~MA
    "(?:(?:headers)|(?:cookies))"\s*:\s*(?:\{[^{}]*\}|\[[^\[\]]*\]|"[^"]*"|[^,}\]]*)(?:,)?\s*
    
    ~~~

For future reference, the aforementioned example renders as:

Alongside lacking syntax highlighting, the typeface is smaller, versus ~~~txt:

~~~RegEx	~~~txt

However, from some diagnosis, this appears to apply to all except ~~~txt, so should this be transferred to github/markup/issues? I hope not, because it's a graveyard of spam.

[lildude]

you're not utilising it inside a footnote:

Ah. Yeah, that has nothing to do with Linguist and would indeed be another thing for markup to fix. I'm not involved with markup but looking at the PRs, it looks like there's no active dev and they're just keeping the lights on.

As this isn't anything in Linguist's control, and is actually a problem with markup, I'm closing this issue. Feel free to open an issue in github/markup if you want.

[RokeJulianLockhart]

@lildude, oh well. Thanks all. Filed github/markup/issues/2000.

[Alhadis]

@Alhadis, I had expected highlighting that was more specific

@RokeJulianLockhart FYI, GitHub's syntax highlighting is limited to a pretty spartan palette. These are the only TextMate scopes supported on GitHub, and even then, they're mapped to one of several similarly-coloured CSS classes that often results in blander, flatter-looking highlighting that differs greatly from a highly-detailed theme, such as the one you're using in VS Code.

I have no control over this. I'd bloody well love too, but I have to work with what we've got. Sorry. 😉