c/highlights : Add a tag for function parameters, global variables, and macro defines

[LeoBras]

Thanks for working on Zed, I am loving using it!
Few requests :)

In C, It would be awesome if we could have different colors for function parameters, global variables and macro defines!

Function parameters:

They are super useful to be easily spotted because we can track faster which parts of the function are being affected by the parameter. I have seen a request for python #17532, and it would look like this:

See how parameter b has a different color than variable i

Global variables:

Sometimes it's important (while you read functions) to make sure to know which variables are global, and which are local, for a very similar reason than function parameters. So it would be awesome to be able to select a color for those.

Sample code with bad color choice, but representing the idea: check a and b

Macro defines:

Telling macros apart from functions can also be very useful, and there are already ways of setting a color on the "#define" part, so it makes sense to match the color on the usage:

On "improved", macro's usage has the same color as it's define

Edit: Adding a new request:

Fade-out disabled code

On VSCode, when code is disabled by a #ifdef, we have the text being faded-out:

(somewhere in the project, CONFIG_SMP is defined, so the second line is disabled and faded-out)

Is there any chance the above features are possible to achieve?

Thanks!
Leo

Originally posted by @LeoBras in #24928

[notpeter]

I believe differentiating between functional parameters and variables, global variables and functional variables, macros and functions all require Zed to have a semantic understanding provided by the LSP and are likely not possible via tree-sitter alone (how Zed currently handles syntax highlighting).

• Support LSP Semantic Tokens #7450

And fade-out of disabled code is:

• Dimming #if / #ifndef / ifdef macro blocks in C/C++ (inactiveRegions) #13089

There is some active work on that front:

• lsp: Add support for clangd's inactiveRegions extension #26146
• Merge clangd's inactiveRegions with existing diagnostics #26737

There is significant interest in #7450, both internally and externally, but I don't have a timeline for supporting this.

I'm going to go ahead and close this as a duplicate of those, but I recommend you 👍 upvote and subscribe to those to track their progress. Thanks for taking the time to write this up.

[LeoBras]

[...] but I recommend you 👍 upvote and subscribe to those to track their progress. Thanks for taking the time to write this up.

I will

With both changes, all requested features would be supported?