rust/tests/ui/dyn-star/dont-unsize-coerce-dyn-star.rs

28 lines
510 B
Rust

//@ run-pass
//@ check-run-results
#![feature(dyn_star)]
//~^ WARN the feature `dyn_star` is incomplete and may not be safe to use and/or cause compiler crashes
trait AddOne {
fn add1(&mut self) -> usize;
}
impl AddOne for usize {
fn add1(&mut self) -> usize {
*self += 1;
*self
}
}
fn add_one(i: &mut (dyn* AddOne + '_)) -> usize {
i.add1()
}
fn main() {
let mut x = 42usize as dyn* AddOne;
println!("{}", add_one(&mut x));
println!("{}", add_one(&mut x));
}