Document `$crate` in macro matcher

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
45/100
Issue type
Documentation
Clarity
Mostly clear
Activity status
Stale
Tech stack
rust
Domain
documentation

Research direction

Start by reproducing the provided macro_rules! example and reviewing the Rust Reference's macro matcher documentation. Document how $crate behaves in a matcher and clarify whether it can be written or matched outside a macro; the example should be explained with the documented behavior.

Written by the indexing model from the issue text.

Description

A-macros

$crate in a macro matcher is the reserved identifier $crate that doesn't have a way to write it outside of a macro (I think?). That is:

macro_rules! m {
    (x) => {
        m!($crate:tt)
    };
    ($crate:tt) => ()
}

fn main() {
    m!(x); // OK
    m!(y); // ERROR
    m!($crate:tt); // ERROR
    m!(crate:tt); // ERROR
}
Dominant language
Rust
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Forks
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Avg merge
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Merged PRs (30d)
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