<code><a href="https://php.net/manual/en/language.types.declarations#language.types.declarations.mixed">mixed</a></code> <span class="var" id="$data">$data<a class="permalink" href="ion/serialize#%24data">#</a></span><br>
PHP value(s).</li>
<li>Optional <a href="ion/Serializer">ion\Serializer</a>|<code><a href="https://php.net/manual/en/language.types.array">array</a></code>|<code><a href="https://php.net/manual/en/language.types.null">null</a></code> <span class="var" id="$serializer">$serializer<a class="permalink" href="ion/serialize#%24serializer">#</a></span> = <code><a href="https://php.net/manual/en/language.types.null">NULL</a></code><br>
-Custom serializer.</li>
+Custom Serializer (options).</li>
</ul><h2 id="Returns:">Returns:<a class="permalink" href="ion/serialize#Returns:">#</a>
</h2><ul>
<li>