### boost::cnv::charconv Converter

| Important
Requires C++17 and up.

The converter is a wrapper around `std::to_chars` and `std::from_chars` and offers great performance with some formatting support. The converter only supports `char`-based strings. Written by Dvir Yitzchaki.

#### Basic Deployment

    #include <boost/convert.hpp>
    #include <boost/convert/charconv.hpp>

    using std::string;
    using boost::convert;

    namespace cnv = boost::cnv;
    namespace arg = boost::cnv::parameter;

    struct cnv::by_default : boost::cnv::charconv {};

    string const     bad_str = "not an int";
    string const     std_str = "-11";
    char const* const  c_str = "-12";
    boost::string_view v_str = boost::string_view(c_str, 2);

    BOOST_TEST( -1 == convert<int>(bad_str).value_or(-1));
    BOOST_TEST(-11 == convert<int>(std_str).value());
    BOOST_TEST(-12 == convert<int>(  c_str).value());
    BOOST_TEST( -1 == convert<int>(  v_str).value_or(0));