title: How do I make a top level xsd:element optional when it contains a complexType?
body: <p>I have this XSD element defined:</p>
  
  <pre><code>&lt;xsd:element name="CU_FIRST_NAME"&gt;
      &lt;xsd:annotation&gt;
          &lt;xsd:documentation&gt;
              The first name of the customer that is getting billed for the order
          &lt;/xsd:documentation&gt;
      &lt;/xsd:annotation&gt;
      &lt;xsd:simpleType&gt;
          &lt;xsd:restriction base="xsd:string"&gt;
              &lt;xsd:maxLength value="50"/&gt;
          &lt;/xsd:restriction&gt;
      &lt;/xsd:simpleType&gt;
  &lt;/xsd:element&gt;
  </code></pre>
  
  <p>I know this could be replaced by a single element, but I have a more complex element (a sequence) that I need to make optional.</p>
  
  <p>Is there a way to make a first-child (i.e. just below <code>&lt;xsd:schema&gt;</code> in the hierarchy) element optional?</p>
  
  <p>To be clear, I'd like to make the entire <code>CU_FIRST_NAME</code> node, along with all of its children, optional.</p>