private function get_page_size(?int $pagesize) : int {
        if (null === $pagesize || $pagesize <= 0) {
            $pagesize = discussion_list_vault::PAGESIZE_DEFAULT;
        }

        return $pagesize;
    }
private function get_page_size(?int $pagesize) : int {
        if (null === $pagesize || $pagesize <= 0) {
            $pagesize = discussion_list_vault::PAGESIZE_DEFAULT;
        }

        return $pagesize;
    }
private function get_page_size ( ? int $ pagesize ) : int { if ( null === $ pagesize || $ pagesize <= 0 ) { $ pagesize = discussion_list_vault :: PAGESIZE_DEFAULT ; } return $ pagesize ; }
Fetch the page size to use when displaying the page.

@param   int         $pagesize The number of discussions to show on the page
@return  int         The normalised page size
Fetch the page size to use when displaying the page .