array( 'type' => 'warning', 'keys' => array( 'posts_per_page', 'numberposts', ), ), ); } /** * Callback to process each confirmed key, to check value. * * @param string $key Array index / key. * @param mixed $val Assigned value. * @param int $line Token line. * @param array $group Group definition. * @return mixed FALSE if no match, TRUE if matches, STRING if matches * with custom error message passed to ->process(). */ public function callback( $key, $val, $line, $group ) { $this->posts_per_page = (int) $this->posts_per_page; if ( $val > $this->posts_per_page ) { return 'Detected high pagination limit, `%s` is set to `%s`'; } return false; } }