tests/ui/traits/const-traits/trait-where-clause-run.rs


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//@ run-pass
//@ compile-flags: -Znext-solver

#![feature(const_trait_impl)]

#[const_trait]
trait Bar {
    fn bar() -> u8;
}

#[const_trait]
trait Foo {
    fn foo() -> u8 where Self: [const] Bar {
        <Self as Bar>::bar() * 6
    }
}

struct NonConst;
struct Const;

impl Bar for NonConst {
    fn bar() -> u8 {
        3
    }
}

impl Foo for NonConst {}

impl const Bar for Const {
    fn bar() -> u8 {
        4
    }
}

impl const Foo for Const {}

fn main() {
    const ANS1: u8 = Const::foo();
    let ans2 = NonConst::foo();

    assert_eq!(ANS1 + ans2, 42);
}