Re: [boost] interest in pair projection iterators?

Lewis Hyatt <lhyatt@Princeton.EDU> writes:

The idea is to define a template class,

template<typename Iterator> class first_iterator_t { Iterator pair_iter; public: first_iterator_t(Iterator const&); /*...*/ };

which overloads operator*() and operator->() to access the element named "first" of the object returned by Iterator::operator*(). (With something analagous for second_iterator_t.) A function named first_iterator() provides a convenient creation function a-la std::make_pair().

Sounds like a job for transform_iterator. http://www.boost.org/libs/iterator/doc/transform_iterator.html -- Dave Abrahams Boost Consulting www.boost-consulting.com