17 lines
307 B
Rust
17 lines
307 B
Rust
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// Expression macros can't expand to a let match guard.
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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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($e:expr) => { let Some(x) = $e }
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//~^ ERROR expected expression, found `let` statement
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}
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fn main() {
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match () {
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() if m!(Some(5)) => {}
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_ => {}
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}
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}
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