"Peter Dimov" <pdimov@mmltd.net> writes:
Sean Parent wrote:
This could have been avoided by defining a separate relation for set/map order, either as a function reachable via ADL, or as a function object, then making sure that it is defined for all standard value types.
Why is this necessary? std::less<> serves us well and avoids the whole ADL mess.
std::less is ambiguous. It could be that you wanted merely the function object representation of operator<, or it could be that you wanted the default map/set ordering relation. It is not clear which of the two std::less is supposed to be.
If shared_ptr doesn't support operator< it's not a problem, is it? You only get into trouble, AFAICT, when operator< and less are both available but they do different things. -- Dave Abrahams Boost Consulting www.boost-consulting.com