rust/example/issue-72793.rs

30 lines
496 B
Rust

// Adapted from rustc ui test suite (ui/type-alias-impl-trait/issue-72793.rs)
#![feature(type_alias_impl_trait)]
mod helper {
pub trait T {
type Item;
}
pub type Alias<'a> = impl T<Item = &'a ()>;
struct S;
impl<'a> T for &'a S {
type Item = &'a ();
}
pub fn filter_positive<'a>() -> Alias<'a> {
&S
}
}
use helper::*;
fn with_positive(fun: impl Fn(Alias<'_>)) {
fun(filter_positive());
}
fn main() {
with_positive(|_| ());
}