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// This test with Cell also indirectly exercises UnsafeCell in dyn*.
//
//@ run-pass
#![feature(dyn_star)]
#![allow(incomplete_features)]
use std::cell::Cell;
trait Rw<T> {
fn read(&self) -> T;
fn write(&self, v: T);
}
impl<T: Copy> Rw<T> for Cell<T> {
fn read(&self) -> T {
self.get()
}
fn write(&self, v: T) {
self.set(v)
}
}
fn make_dyn_star() -> dyn* Rw<usize> {
Cell::new(42usize) as dyn* Rw<usize>
}
fn main() {
let x = make_dyn_star();
assert_eq!(x.read(), 42);
x.write(24);
assert_eq!(x.read(), 24);
}
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