On Tue, Sep 22, 2009 at 3:11 PM, Archie14 <admin@tradeplatform.us> wrote:

If a given class defines operator + and there is a vector of instances of that
class:
how I can use std::accumulate to count sum against this vector for the
elements that satisfy certain conditions?
class A
{
 public:
   A(useinsum) : _useinsum(useinsum) {};
   bool useinsum() {return _useinsum;}
   int operator + (int a) {return _i + a;}
 private
   bool _useinsum;
   int _i;
}

std::vector<A> lst;

will that work?
std::accumulate(lst.begin(), lst.end(), 0, boost::lambda::bind(&A::useinsum,
boost::lambda::_1) == false)