While I don't have an RFC your you (I'm not the same person), here's an interesting thread on maybe tweaking the interface: https://internals.rust-lang.org/t/is-custom-allocators-the-r...

And here's the working group's repo: https://github.com/rust-lang/wg-allocators

I'm not sure there's an up-to-date RFC, but here's what it looks like: https://doc.rust-lang.org/nightly/std/boxed/struct.Box.html#...

Will they avoid the Transparent Comparator fudge that C++ has because the allocator is part of the type?

https://stackoverflow.com/questions/20317413/what-are-transp...

Could you elaborate on what this is, exactly?

In short, it allows a std::map<K, V> to be queried with a type that isn't K. For example,

    std::map<std::string, int> m;
    std::string_view sv = "mykey";
    auto&& iter = m.find(sv);

Oh, rust already has that.