ler Compatibility:</strong></span> This trait requires
        the C++11 features <code class="computeroutput"><span class="keyword">decltype</span></code>
        variadic templates and SFINAE-expression support for full support. While
        there is some fallback code for cases where this is not the case, the trait
        should really be considered broken in that case. The header will define the
        macro <code class="computeroutput"><span class="identifier">BOOST_TT_IS_CONSTRUCTIBLE_CONFORMING</s