rust/tests/ui/rfcs/rfc-2632-const-trait-impl/trait-default-body-stability.rs
2023-12-19 04:28:21 +00:00

51 lines
1.1 KiB
Rust

// known-bug: #110395
#![feature(staged_api)]
#![feature(const_trait_impl, effects)]
#![feature(const_t_try)]
#![feature(const_try)]
#![feature(try_trait_v2)]
#![stable(feature = "foo", since = "1.0")]
use std::ops::{ControlFlow, FromResidual, Try};
#[stable(feature = "foo", since = "1.0")]
pub struct T;
#[stable(feature = "foo", since = "1.0")]
#[rustc_const_unstable(feature = "const_t_try", issue = "none")]
impl const Try for T {
type Output = T;
type Residual = T;
fn from_output(t: T) -> T {
t
}
fn branch(self) -> ControlFlow<T, T> {
ControlFlow::Continue(self)
}
}
#[stable(feature = "foo", since = "1.0")]
#[rustc_const_unstable(feature = "const_t_try", issue = "none")]
impl const FromResidual for T {
fn from_residual(t: T) -> T {
t
}
}
#[stable(feature = "foo", since = "1.0")]
#[const_trait]
pub trait Tr {
#[stable(feature = "foo", since = "1.0")]
fn bar() -> T {
T?
// Should be allowed.
// Must enable unstable features to call this trait fn in const contexts.
}
}
fn main() {}