mirror of https://github.com/rust-lang/rust
46 lines
774 B
Rust
46 lines
774 B
Rust
//@ run-pass
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#![feature(box_patterns)]
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use std::ops::{Deref, DerefMut};
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struct X(Box<isize>);
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static mut DESTRUCTOR_RAN: bool = false;
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impl Drop for X {
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fn drop(&mut self) {
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unsafe {
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assert!(!DESTRUCTOR_RAN);
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DESTRUCTOR_RAN = true;
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}
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}
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}
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impl Deref for X {
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type Target = isize;
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fn deref(&self) -> &isize {
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let &X(box ref x) = self;
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x
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}
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}
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impl DerefMut for X {
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fn deref_mut(&mut self) -> &mut isize {
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let &mut X(box ref mut x) = self;
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x
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}
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}
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fn main() {
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{
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let mut test = X(Box::new(5));
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{
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let mut change = || { *test = 10 };
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change();
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}
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assert_eq!(*test, 10);
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}
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assert!(unsafe { DESTRUCTOR_RAN });
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}
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