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33 lines
610 B
Rust
33 lines
610 B
Rust
// run-pass
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#![feature(rustc_attrs)]
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use std::sync::Arc;
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trait Foo {
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fn get(&self) -> [u8; 2];
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}
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impl Foo for [u8; 2] {
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fn get(&self) -> [u8; 2] {
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*self
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}
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}
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struct Bar<T: ?Sized>(T);
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fn unsize_fat_ptr<'a>(x: &'a Bar<dyn Foo + Send + 'a>) -> &'a Bar<dyn Foo + 'a> {
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x
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}
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fn unsize_nested_fat_ptr(x: Arc<dyn Foo + Send>) -> Arc<dyn Foo> {
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x
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}
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fn main() {
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let x: Box<Bar<dyn Foo + Send>> = Box::new(Bar([1,2]));
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assert_eq!(unsize_fat_ptr(&*x).0.get(), [1, 2]);
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let x: Arc<dyn Foo + Send> = Arc::new([3, 4]);
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assert_eq!(unsize_nested_fat_ptr(x).get(), [3, 4]);
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}
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