Add proc-macro to derive CheckCodePrefix

[messense]

IMO a derive macro is a natural way to generate new code, and it reduces the chance of merge conflicts.

[charliermarsh]

Yeah this makes a lot of sense, thank you. My main critique of macros like this is that they hurt the IDE experience, since (e.g.) CheckCodePrefix will no longer autocomplete in the editor... But this does seem more natural, and it also solves some of the bootstrapping problems that we have today, whereby we can't reference check code prefixes before generating them, etc.

[charliermarsh]

(Nice work.)

[not-my-profile]

My main critique of macros like this is that they hurt the IDE experience, since (e.g.) CheckCodePrefix will no longer autocomplete in the editor...

Autocompletion works fine for me using rust-analyzer, which has rust-analyzer.procMacro.enable enabled by default. Are you using another language server for rust? I highly recommend rust-analyzer.

[messense]

I think intellij-rust also works fine with derive macros now: intellij-rust/intellij-rust#6908

org.rust.macros.proc.derive - enables expansion of derive procedural macros. Enabled by default

[charliermarsh]

I use IntelliJ, for me I still don't see expansion unfortunately:

[messense]

That's odd, it works for me in CLion, maybe you need to enable the Expand macros option

[charliermarsh]

I think I had to enable some more stuff in "Experimental features" -- looks like it's working now! Amazing! Thanks both!