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// Regression test for #79457.
#![feature(min_specialization)]
use std::any::Any;
pub trait Tr {
fn method(self) -> Box<dyn Any + 'static>;
fn other(self);
}
impl<T: Any + 'static> Tr for T {
default fn method(self) -> Box<dyn Any + 'static> {
Box::new(self)
}
default fn other(self) {}
}
impl<'a> Tr for &'a i32 {
//~^ ERROR does not fulfill the required lifetime
fn other(self) {}
}
fn promote_to_static<'a>(i: &'a i32) -> &'static i32 {
*i.method().downcast().unwrap()
}
struct Wrapper<'a>(&'a i32);
impl<'a> Tr for Wrapper<'a> {
//~^ ERROR does not fulfill the required lifetime
fn other(self) {}
}
fn promote_to_static_2<'a>(w: Wrapper<'a>) -> Wrapper<'static> {
*w.method().downcast().unwrap()
}
fn main() {
let i = Box::new(100_i32);
let static_i: &'static i32 = promote_to_static(&*i);
drop(i);
println!("{}", *static_i);
let j = Box::new(200_i32);
let static_w: Wrapper<'static> = promote_to_static_2(Wrapper(&*j));
drop(j);
println!("{}", *static_w.0);
}
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