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#![feature(const_trait_impl)]
#![feature(generic_arg_infer)]
#![feature(generic_const_exprs)]
#![allow(incomplete_features)]
struct Foo<const N: usize>;
impl<const N: usize> Foo<N> {
fn add<A: ~const Add42>(self) -> Foo<{ A::add(N) }> {
//~^ ERROR `~const` is not allowed here
//~| ERROR the trait bound `A: const Add42` is not satisfied
Foo
}
}
#[const_trait]
trait Add42 {
fn add(a: usize) -> usize;
}
impl const Add42 for () {
fn add(a: usize) -> usize {
a + 42
}
}
fn bar<A: ~const Add42, const N: usize>(_: Foo<N>) -> Foo<{ A::add(N) }> {
//~^ ERROR `~const` is not allowed here
//~| ERROR the trait bound `A: const Add42` is not satisfied
Foo
}
fn main() {
let foo = Foo::<0>;
let foo = bar::<(), _>(foo);
let _foo = bar::<(), _>(foo);
}
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