mirror of https://github.com/rust-lang/rust
26 lines
572 B
Rust
26 lines
572 B
Rust
#![feature(associated_type_defaults)]
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use std::ops::Deref;
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trait UnsafeCopy {
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type Copy<T>: Copy = Box<T>;
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//~^ ERROR the trait bound `Box<T>: Copy` is not satisfied
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//~^^ ERROR the trait bound `T: Clone` is not satisfied
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fn copy<T>(x: &Self::Copy<T>) -> Self::Copy<T> {
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*x
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}
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}
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impl<T> UnsafeCopy for T {}
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fn main() {
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let b = Box::new(42usize);
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let copy = <()>::copy(&b);
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let raw_b = Box::deref(&b) as *const _;
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let raw_copy = Box::deref(©) as *const _;
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// assert the addresses.
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assert_eq!(raw_b, raw_copy);
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}
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