YQL data table for http://stackoverflow.com/questions/15249380/is-it-possible-to-filter-the-descendant-elements-returned-from-an-xpath-query

so-15249380.xml

<table xmlns="http://query.yahooapis.com/v1/schema/table.xsd">
  <meta>
    <author>Peter Cowburn</author>
    <documentationURL>http://stackoverflow.com/questions/15249380/is-it-possible-to-filter-the-descendant-elements-returned-from-an-xpath-query</documentationURL>
    <sampleQuery>select * from {table} where url="http://www.yahoo.com"</sampleQuery>
  </meta>
  <bindings>
    <select itemPath="" produces="XML">
      <urls>
        <url></url>
      </urls>
      <inputs>
        <key id="url" type="xs:string" paramType="variable" required="true" />
        <key id="xpath" type="xs:string" paramType="variable" default="//form[@action]" />
        <key id="filter" type="xs:string" paramType="variable" default="descendant::label|descendant::input|descendant::select|descendant::textarea" />
      </inputs>
      <execute>
        <![CDATA[
        var elements = y.query("select * from html where url=@u and xpath=@x", {u: url, x: xpath}).results.elements();
        var results = <url url={url}></url>;
        for each (element in elements) {
            var result = element.copy();
            result.setChildren("");
            result.normalize();
            for each (descendant in y.xpath(element, filter)) {
                result.node += descendant;
            }
            results.node += result;
        }
        response.object = results;
        ]]>
      </execute>
    </select>
  </bindings>
</table>