On 07/08/2004 12:58 PM, David B. Held wrote:
This is what I would like to do:
template <class P1, class P2> struct sp { template <typename T> struct nested { }; };
template <typename T> struct less;
template <class P1, class P2, typename T> struct less<sp<P1, P2>::nested<T> > : binary_function<...> { bool operator()(...); };
However, it doesn't work. From my research, it seems that the problem is that T is in a non-deduced context, but I don't see why that would be an issue, since this is how I expect it to get instantiated:
less<sp<p1, p2>::nested<int> > comp;
Thus, I don't see any deduction as being necessary, but obviously I don't exactly understand how to get what I want.
I very much sympathize with you; however, I have no answers :( I went through the same confusion with my managed_ptr's nested ownership template class. It was discussed here: http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=1044dnuf7ojhpc0%40corp.supernews.com In the above, David Abraham also expressed surprise at the need for deduction. A proposed standard change was also discussed here: http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=1072lb8ira3jg41%40corp.supernews.com However, there was no acknowledgement that it would work :(