Re: [NonGNU ELPA] new package: clangd-inactive-regions

[Stefan Kangas <stefankangas@gmail.com>]

Filippo Argiolas <filippo.argiolas@gmail.com> writes:

> Just wanted to check if there's any interest in including my little
> package in NonGNU ELPA:
>
> https://github.com/fargiolas/clangd-inactive-regions.el
>
> It's an eglot extension that listens to clangd inactiveRegions
> notifications and shades inactive code accordingly. It's useful to
> highlight disabled code sections in a LSP aware way, honoring current
> building options and defines.
>
> It started as little more than an experiment but I've been using it on
> the day job with a ifdef-heavy codebase and it has been serving me
> well for more than a year. Thought it could be useful to other people
> too.
>
> I'm not exactly an elisp expert, so feedback is very welcome!

Thanks.  It sounds useful, so I think we should add it.  I'm interested
to see how well this will work in Emacs itself, but I didn't have time
to test it yet.

How would you feel about adding this package to GNU ELPA instead?  The
main requirement would be copyright assignments to the FSF from all
current and future contributors.  I see that you're the sole contributor
for now.  I think that would be useful, since there seems to be a plan
to suggest adding this to the LSP protocol, in which case we'd really
want this in Eglot itself, I think.[1]

One comment from reading the README is that it would be helpful to add a
few sentences there about what the inactiveRegion LSP extension does.
For example, it could say something like this:

    "inactiveRegions" is a clangd-specific extension to the LSP protocol
    that allows LSP clients to hide code that is in a currently inactive
    preprocessor branch.

...or something along those lines.

On a side note, I also read this in the README:

    As far as I know Emacs doesn't have a way to set foreground text
    opacity. Best would be a face attribute so that you can set it in an
    overlay covering each inactive region and be done with
    it. Unfortunately there is no attribute for this yet.

Would such a feature be hard to add to the display engine?  Eli?

Footnotes:
[1]  https://github.com/clangd/clangd/issues/132#issuecomment-1722327517