#### Supported String Types

##### Wide String

    BOOST_TEST(L"11111110" == convert<wstring>(254, cnv(arg::base = cnv::base::bin)).value());
    BOOST_TEST(     L"254" == convert<wstring>(254, cnv(arg::base = cnv::base::dec)).value());
    BOOST_TEST(      L"FE" == convert<wstring>(254, cnv(arg::base = cnv::base::hex)).value());
    BOOST_TEST(     L"376" == convert<wstring>(254, cnv(arg::base = cnv::base::oct)).value());

    BOOST_TEST(-1 == convert<int>(L" 12", cnv(arg::skipws = false)).value_or(-1));
    BOOST_TEST(12 == convert<int>(L" 12", cnv(arg::skipws =  true)).value_or(-1));