This is probably still a bit of a long shot in Rust's developing type system, but is there a way to filter a tuple or hlist of references based on whether those types implement one or ideally multiple traits? I'm wondering if there's some unholy combination of frunk, hlists, facet, and/or feature(min_specialization) (or other relatively stable/safe nightly features) to do this.

Essentially a function where I feed in (&FooImplementsTraits, &BarDoesntImplement, &BazImplementsTraits) and get out (&FooImplementsTraits, &BazImplementsTraits) (or an HList equivalent). Is that possible in Rust's type system at this point?

I know there's this trick that uses the preference for inherent methods, but that wouldn't work at the generic level over tuples/hlists. For use case context, I'm trying to work on improvements to gecs to be less macro-dependent, but I'm stuck on being able to filter archetypes by what component types they hold.

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