rust/tests/ui/rfcs/rfc-2632-const-trait-impl/const-impl-trait.rs

57 lines
1.1 KiB
Rust

//@ known-bug: #110395
// Broken until we have `&T: const Deref` impl in stdlib
#![allow(incomplete_features)]
#![feature(
const_trait_impl,
effects,
const_cmp,
)]
use std::marker::Destruct;
const fn cmp(a: &impl ~const PartialEq) -> bool {
a == a
}
const fn wrap(x: impl ~const PartialEq + ~const Destruct)
-> impl ~const PartialEq + ~const Destruct
{
x
}
#[const_trait]
trait Foo {
fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
}
impl const Foo for () {
fn huh() -> impl ~const PartialEq + ~const Destruct + Copy {
123
}
}
const _: () = {
assert!(cmp(&0xDEADBEEFu32));
assert!(cmp(&()));
assert!(wrap(123) == wrap(123));
assert!(wrap(123) != wrap(456));
let x = <() as Foo>::huh();
assert!(x == x);
};
#[const_trait]
trait T {}
struct S;
impl const T for S {}
const fn rpit() -> impl ~const T { S }
const fn apit(_: impl ~const T + ~const Destruct) {}
const fn rpit_assoc_bound() -> impl IntoIterator<Item: ~const T> { Some(S) }
const fn apit_assoc_bound(_: impl IntoIterator<Item: ~const T> + ~const Destruct) {}
fn main() {}