../../nb/ds/NamedData.html">NamedData</a>&lt;<span class="type">T</span>&gt;&gt;,</span> <span style="white-space:nowrap">oldKey:<a class="type" title="String - The basic String class." href="../../String.html">String</a>,</span> <span style="white-space:nowrap">newKey:<a class="type" title="String - The basic String class." href="../../String.html">String</a></span>):<a class="type" title="Null - Null&amp;lt;T&amp;gt; is a wrapper that can be used to make the basic types Int, Float and Bool nullable on sta