tests/ui/traits/const-traits/specialization/specialize-on-conditionally-const.rs


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// Tests that `[const]` trait bounds can be used to specialize const trait impls.
// cc #95186

//@ check-pass

#![feature(const_trait_impl)]
#![feature(rustc_attrs)]
#![feature(min_specialization)]

#[const_trait]
#[rustc_specialization_trait]
trait Specialize {}

#[const_trait]
trait Foo {
    fn foo();
}

impl<T> const Foo for T {
    default fn foo() {}
}

impl<T> const Foo for T
where
    T: [const] Specialize,
{
    fn foo() {}
}

#[const_trait]
trait Bar {
    fn bar() {}
}

impl<T> const Bar for T
where
    T: [const] Foo,
{
    default fn bar() {}
}

impl<T> const Bar for T
where
    T: [const] Foo,
    T: [const] Specialize,
{
    fn bar() {}
}

fn main() {}