| My own personal view (not that of chair) is that if std::less<T>(l,r) and"fails" in which sense? It is certainly true in the current standards
| "l < r" are
| both defined, then they should yield the same answer.
| Which fails for pointers.
these expressions are both defined when 'l' and 'r' are related
addresses (relative to the same object), which was exactly my point.