rust/tests/ui/regions/regions-early-bound-lifetime-in-assoc-fn.rs
2023-01-11 09:32:08 +00:00

36 lines
787 B
Rust

// run-pass
#![allow(unused_imports)]
// Test that we are able to compile calls to associated fns like
// `decode()` where the bound on the `Self` parameter references a
// lifetime parameter of the trait. This example indicates why trait
// lifetime parameters must be early bound in the type of the
// associated item.
// pretty-expanded FIXME #23616
use std::marker;
pub enum Value<'v> {
A(&'v str),
B,
}
pub trait Decoder<'v> {
fn read(&mut self) -> Value<'v>;
}
pub trait Decodable<'v, D: Decoder<'v>> {
fn decode(d: &mut D) -> Self;
}
impl<'v, D: Decoder<'v>> Decodable<'v, D> for () {
fn decode(d: &mut D) -> () {
match d.read() {
Value::A(..) => (),
Value::B => Decodable::decode(d),
}
}
}
pub fn main() { }