Description:
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Support Response parsing using SolrDocument parsing mode, serialization/unserialization of children

API:
bool  SolrDocument::hasChildDocuments( void )
array SolrDocument::getChildDocuments( void )
int   SolrDocument::getChildDocumentsCount( void )


Test script:
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require_once "bootstrap.inc";

$fixtureXml = file_get_contents(EXAMPLE_RESPONSE_XML_2);

$response = SolrUtils::digestXmlResponse($fixtureXml, SolrResponse::PARSE_SOLR_DOC);
print_r($response->response);