mirror of https://github.com/rust-lang/rust
22 lines
472 B
Rust
22 lines
472 B
Rust
//@ run-pass
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#![feature(deref_patterns)]
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#![allow(incomplete_features)]
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fn main() {
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let b = Box::new("aaa".to_string());
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let f = || {
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let deref!(ref s) = b else { unreachable!() };
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assert_eq!(s.len(), 3);
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};
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assert_eq!(b.len(), 3);
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f();
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let mut b = Box::new("aaa".to_string());
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let mut f = || {
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let deref!(ref mut s) = b else { unreachable!() };
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s.push_str("aa");
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};
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f();
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assert_eq!(b.len(), 5);
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}
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