/** * Evaluates the GRPAH clause if there is one. Checks if * the GRAPH clause contains an IRI, variable or nothing. * Returns an array which contains the graphs that has to be matched. * * @param GraphPattern $pattern * @param Array $graphlist * @return Array */ protected function _checkGraphs(&$pattern, $graphlist) { $gr = $pattern->getGraphname(); if ($gr instanceof Resource) { if ($graphlist[0] == null || in_array($gr, $graphlist)) { $newGraphList['list'][] = $gr; $newGraphList['var'][] = null; } else { return false; } } elseif (is_string($gr)) { $newGraphList['list'] = $graphlist; $newGraphList['var'][] = $gr; } else { $newGraphList['list'] = $graphlist; $newGraphList['var'][] = null; } return $newGraphList; }