Hi Chris, On Nov 20, 2007 9:07 AM, Chris Weed <chrisweed@gmail.com> wrote:
Recently, I've implemented a simple utility which allows users to select the nth element of an STL pair / Boost.Tuple in conjunction with STL algorithms. This allows precisely the following usage semantics:
Hi, It would also be nice to make this work with transform_iterator. For example
#include <boost/iterator/transform_iterator.hpp> std::list<boost::tuple<double, double, double> > coord_list; coord_list.push_back(boost::make_tuple(1.0, 2.0, 3.0)); coord_list.push_back(boost::make_tuple(4.0, 5.0, 6.0));
std::transform( boost::make_transform_iterator(coord_list.begin(),boost::select<0>()), boost::make_transform_iterator(coord_list.end(),boost::select<0>()), std::ostream_iterator<double>(std::cout, " ")); // output "1.0 4.0 "
This would require your select functor conforming to result_of, and transform_iterator using it.
I've been trying, and it's taking me a while to first of all make it result_of compliant. Maybe something worth spending more time on, I'm not sure. I'll send an update if/when I come up with something to this effect. Have a good day! -- Dean Michael C. Berris Software Engineer, Friendster, Inc. [http://cplusplus-soup.blogspot.com/] [mikhailberis@gmail.com] [+63 928 7291459] [+1 408 4049523]