ass="special">/</span><span class="identifier">utility</span><span class="special">/</span><span class="identifier">base_from_member</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>

<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">cstddef</span><span class="special">&gt;</span>  <span class="comment">/* for NULL */</span>

<span class="keyword">struct</span> <span class="identifier">an_int</span>
<sp