27 lines
496 B
Rust
27 lines
496 B
Rust
// Tests that specializing trait impls must be at least as const as the default impl.
|
|
|
|
#![feature(const_trait_impl)]
|
|
#![feature(min_specialization)]
|
|
|
|
#[const_trait]
|
|
trait Value {
|
|
fn value() -> u32;
|
|
}
|
|
|
|
impl<T> const Value for T {
|
|
default fn value() -> u32 {
|
|
0
|
|
}
|
|
}
|
|
|
|
struct FortyTwo;
|
|
|
|
impl Value for FortyTwo { //~ ERROR cannot specialize on const impl with non-const impl
|
|
fn value() -> u32 {
|
|
println!("You can't do that (constly)");
|
|
42
|
|
}
|
|
}
|
|
|
|
fn main() {}
|