Php/docs/solrcollapsefunction.tostring
From Get docs
SolrCollapseFunction::__toString
(PECL solr >= 2.2.0)
SolrCollapseFunction::__toString — Returns a string representing the constructed collapse function
Description
public SolrCollapseFunction::__toString ( ) : string
Returns a string representing the constructed collapse function
Parameters
This function has no parameters.