| #![allow(incomplete_features)] | |
| #![feature(const_trait_impl, effects, try_trait_v2)] | |
| use std::ops::FromResidual; | |
| impl<T> const FromResidual for T { | |
| //~^ ERROR const `impl` for trait `FromResidual` which is not marked with `#[const_trait]` | |
| //~| type parameter `T` must be used as the type parameter for some local type | |
| fn from_residual(t: T) -> _ { | |
| //~^ the placeholder `_` is not allowed | |
| t | |
| } | |
| } | |
| fn main() {} |