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