frozen::unordered_multiset?

[davidson16807]

What would be required to create the frozen equivalent of unordered_multiset?

I'm asking since I think the existence of such a thing could allow for creating nice and easy compile-time unit libraries akin to mpusz/units or benri:

constexpr frozen::unordered_multiset<frozen::string, int, 1> mass = {{"mass", 1}};
constexpr frozen::unordered_multiset<frozen::string, int, 2> acceleration = {{"length", 1}, {"time", -2}};
constexpr auto force = combine(mass, acceleration);

Personally, if I'm writing a software framework that relies on a dimensional type system I'd much rather rely on a low lying abstraction like a frozen::unordered_multiset rather than force users to add one of these units libraries to their list of dependencies.

[serge-sans-paille]

Let's consider the case of an unordered_multimap that brings the unordered_multiset for free. An option could be to implement it as an unordered_multimap with a cvector with the appropriate bound derived from the intializer.