name</span> DerivIn<span class="special">&gt;</span> 
    <span class="identifier">boost</span><span class="special">::</span><span class="identifier">disable_if</span><span class="special">&lt;</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">is_same</span><span class="special">&lt;</span> <span class="identifier">DerivIn</span><span class="special">,</span> <span class="identifier">time_type</span> <span class="special">&gt;</span><span class="special">,<