Hello, i have some questions:
1) Why min_element give me errors without BOOST_RANGE_ENABLE_CONCEPT_ASSERT defined 0? Is it uses only for make error messages more readable? Is it   safe to define it to 0?
#include <vector>
//#define BOOST_RANGE_ENABLE_CONCEPT_ASSERT 0
#include <boost/range.hpp>
#include <boost/range/adaptors.hpp>
#include <boost/range/algorithm.hpp>
#include <boost/range/numeric.hpp>
#include <boost/bind.hpp>

struct foo{
int x;
};

int main()
{
using namespace boost::adaptors; using boost::bind;

std::vector<foo> vec;
auto rng = vec | transformed(bind(&foo::x, _1));
boost::accumulate(rng, 0); // ok 
boost::min_element(rng); // error
}

2) Why only logical operators overloaded for boost::bind and arithmetic one are not? Is it safe to define it manually with BOOST_BIND_OPERATOR?