howSeparator</code> to get output <code>child(3, 4) is null</code> which
is more polished than <code>child(3, 4): is null</code>.
<pre class="language-dart"><code class="language-dart">DiagnosticsProperty&lt;IconData&gt;('icon', icon, ifNull: '&lt;empty&gt;', showName: false).toString()
</code></pre>
Shows using <code>showName</code> to omit the property name as in this context the
property name does not add useful information.</li>
</ul>
<p><code>ifNull</code>, <code>ifEmpty</code>, <code>unit</code>, and 