I think the problem here is more that the semantics are documented in the "documentation", but are contrary to the intuition derived from the semantics in the t

I think the problem here is more that the semantics are documented in the "documentation", but are contrary to the intuition derived from the semantics in the type system. `.contains()` is only implemented for `Range<Idx: PartialOrd>`, which to me implies that when checking whether a value is contained in the Range, it has enough knowledge about the ordering of numbers that it should be able to still do a bounds check on reversely ordered numbers.