Using a derive proc-macro from macro_rules!() results in a compile error about `self` parameter. about rust HOT 3 CLOSED

I have a minimal example. How should I upload it?

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I prefer code blocks in issue comments like you did above. Even if it's multiple files, then at least it doesn't rely on a commit staying around in someone's repo.

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While trying to simplify the proc-macro, I think I figured out what is going on. The issue is the following line in the proc-macro above:

quote_spanned! {f.span()=> crate::BitwiseEq::bitwise_eq(&self.#index, &other.#index) }

When I changed quote_spanned! to quote!, it works. The f.span() refers to the i32 token in impl_bitwise5!(Wrap5, i32);. When he compiler sees the self in the expanded code, and the span for which is outside the macro_rules, it seems to be looking for self outside the macro_rules! call-site and errors out.

I don't fully understand how spans interact with macro hygiene, but it makes sense for the compiler to show some kind of error. But the error was very confusing.

Anyways, I know how to fix my code. I'll close this issue.

Thanks for looking into it!

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