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// Taken from https://github.com/rust-lang/rust/issues/44454#issuecomment-1332781290
use std::any::Any;
trait Animal<X>: 'static {}
trait Projector {
type Foo;
}
impl<X> Projector for dyn Animal<X> {
type Foo = X;
}
fn make_static<'a, T>(t: &'a T) -> &'static T {
let x: <dyn Animal<&'a T> as Projector>::Foo = t;
let any = generic::<dyn Animal<&'a T>, &'a T>(x);
//~^ ERROR: lifetime may not live long enough
any.downcast_ref::<&'static T>().unwrap()
}
fn generic<T: Projector + Animal<U> + ?Sized, U>(x: <T as Projector>::Foo) -> Box<dyn Any> {
make_static_any(x)
}
fn make_static_any<U: 'static>(u: U) -> Box<dyn Any> {
Box::new(u)
}
fn main() {
let a = make_static(&"salut".to_string());
println!("{}", *a);
}
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