Type erase a const generic in a trait

help
1

If you have a trait with a lifetime, you can quite simply and expressively do:

trait WithLifetime<'a> {}

trait Erased: for<'a> WithLifetime<'a> {}

And if you have one with an actual type you can go with:

trait NamesType<T> {}

trait AsAssociated: NamesType<Self::T> {
    type T;
}

But trying to do similarly with a const generic is just.... broken:

#![feature(generic_const_exprs)]
trait NamesConst<const N: usize> {}

trait SelectConst: NamesConst<{ Self::N }>
where
    [(); { Self::N }]: ,
{
    const N: usize;
}

Hooray! All that fussing about with nightly and adding weird bounds just to end up with a cycle detected in compilation...
[playground]

I know const generics are one of the targets for Rust 2024, but is there any way to work around
this currently? Or, am I just going to have to carry around an extra const N: usize generic parameter for a while longer?

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