s="keyword">nullptr</span> <span class="special">)</span>
<span class="special">{</span>
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span class="identifier">indent_</span><span class="special">;</span>
    <span class="keyword">if</span><span class="special">(!</span> <span class="identifier">indent</span><span class="special">)</span>
        <span class="identifier">indent</span> <span class="special">=</span> <span class="special">&amp;</s