Comment by monkeyelite

> internal implementation of std::map > abusing the ordering function

That's the thing about C++. It's not abuse - any strict weak ordering is valid. You are follow the rules and it's guaranteed mathematically to produce correct results.

> capable of comparing any two elements of the key space

You get to define the domain of keys which is almost always a restriction of the possible bits of the key. For example, you can use floats as keys even though nan would break.

> Nor is it intuitive

Intuitive too often means "I haven't seen it before" which is a bias to not learn new approaches of programming. All sufficiently technical knowledge is unintuitive.

- it relies on understanding how balanced trees are typically implemented.

No it doesn't. It's documented API.

> exploit the transitive rule for total orders to avoid unnecessarily performing comparisons

Yes, the comparison must satisfy transitivity. This doesn't violate that.

> I know whining about downvotes is frowned upon here

I downvote low-quality, not to disagree (I did not downvote).