Nit: std::collections::HashSet

[mooman219]

I noticed this library uses std::collections::HashSet. Is there a reason for that over hashbrown::HashSet? Standard's implementation is backed by hashbrown, so functionally there's no difference. The current code forces a std import.

[notgull]

The issue (I think?) is that, if you use hashbrown, you bring in not only that crate as a dependency, but also whatever hasher you decide to use with it. If that isn't an issue, I would support using hashbrown for no_std.

[ajtribick]

Another question is whether another collection type might be possible here, e.g. change to use BTreeSet (or even Vec), in which case you'd only need alloc.