mirror of https://github.com/rust-lang/rust
27 lines
663 B
Rust
27 lines
663 B
Rust
// Ensure if let guards can be used in constant expressions.
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//@ build-pass
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#![feature(if_let_guard)]
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const fn match_if_let(x: Option<i32>, y: Option<i32>) -> i32 {
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match x {
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None if let Some(a @ 5) = y => a,
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Some(z) if let (Some(_), 12) = (y, z) => 2,
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_ => 3,
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}
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}
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const ASSERTS: usize = {
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assert!(match_if_let(None, Some(5)) == 5);
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assert!(match_if_let(Some(12), Some(3)) == 2);
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assert!(match_if_let(None, Some(4)) == 3);
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assert!(match_if_let(Some(11), Some(3)) == 3);
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assert!(match_if_let(Some(12), None) == 3);
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assert!(match_if_let(None, None) == 3);
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0
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};
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fn main() {
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let _: [(); ASSERTS];
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}
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