Initialising empty nodesets

If the nodeset referred to is empty then the node being copied is created as a child of the insert handler's context node (if you are not clear on the evaluation context then read this):

<xf:group ref="list">
  <xf:repeat nodeset="y">
    <xf:output ref="." />
  </xf:repeat>

  <xf:trigger>
    <xf:label>Add new 'x'</xf:label>
    <xf:action ev:event="DOMActivate">
      <!--
        The evaluation context here is still 'list', from
        the xf:group, above.
      -->
      <xf:insert nodeset="y" origin="../templates/x" />
    </xf:action>
  </xf:trigger>
</xf:group>

In many situations there may be no natural 'context', such as the group in the previous example. In these circumstances we use the context attribute to set a context explicitly:

<xf:insert context="list" nodeset="y" origin="../templates/x" />

Note that the @origin value is also evaluated relative to the evaluation context.