On Feb 14, 2005, at 2:52 PM, Jonathan Turkanis wrote:
Howard Hinnant wrote:
I think we could do better, but it would be stretching TR1 (which I think is good).
I think any compatible tuple-like type should be convertible to tuple (pair, array, maybe complex?, anything else that declares itself tuple-like and implements the tuple interface). Furthermore, I think is_convertible should answer correctly, even for negative cases (for those pair that are not convertible to a 2-tuple).
I'd definitely like some standard way for a type to declare itself tuple-like. Why didn't it make it into TR1?
I use a version of it here, to allow arbitrary tuple-like types to take advantage of a form of tuple i/o:
http://www.kangaroologic.com/format_lite/libs/format_lite/doc/? path=4.2.5
<nod> I use is_tuple_like too. It was in the original proposal. It got dumped somewhere along the way. I'm not sure why. When tuple was first voted into TR1, enable_if was brand new and pretty exotic. Parts of tuple that benefited from (and depended on) enable_if were dumped. It may be that is_tuple_like got thrown out along with that dump. Imho, tuple did not benefit from that exercise. We get another shot at it for C++0X though. So existing practice that is a little better than TR1 can still help. -Howard