mirror of https://github.com/rust-lang/rust
19 lines
431 B
Rust
19 lines
431 B
Rust
// Macros can be used for (parts of) the pattern and expression in an if let guard
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//@ check-pass
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#![feature(if_let_guard)]
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#![feature(let_chains)]
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macro_rules! m {
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(pattern $i:ident) => { Some($i) };
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(expression $e:expr) => { $e };
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}
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fn main() {
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match () {
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() if let m!(pattern x) = m!(expression Some(4)) => {}
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() if let [m!(pattern y)] = [Some(8 + m!(expression 4))] => {}
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_ => {}
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}
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}
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