Re: [boost] [range] Best way to count the elements in a filtered range?

On 19 June 2013 11:41, Gonzalo BG wrote:

I wonder what is the recommended way to count the elements in a filtered range.

Let range be a random access range, and filter the result of filtered(predicate),

auto filtered_range = range | filter; count_if( filtered_range, [](const&){ return true; }); // (& omitted in lambda)

I think boost::size() is what you want. size_t s = boost::size(range | filter); See: http://www.boost.org/doc/libs/1_53_0/boost/range/size.hpp -- Darren