rust/tests/ui/variance/variance-covariant-arg-trai...

28 lines
603 B
Rust

#![allow(dead_code)]
// Test that even when `T` is only used in covariant position, it
// is treated as invariant.
trait Get<T> {
fn get(&self) -> T;
}
fn get_min_from_max<'min, 'max, G>()
where 'max : 'min, G : Get<&'max i32>
{
// Previously OK, now an error as traits are invariant.
impls_get::<G,&'min i32>()
//~^ ERROR lifetime may not live long enough
}
fn get_max_from_min<'min, 'max, G>()
where 'max : 'min, G : Get<&'min i32>
{
impls_get::<G,&'max i32>()
//~^ ERROR lifetime may not live long enough
}
fn impls_get<G,T>() where G : Get<T> { }
fn main() { }