SimplePie::set_feed_url( string|string[] $url ): void

765    public function set_feed_url($url)766    {767        $this->multifeed_url = [];768        if (is_array($url)) {769            trigger_error('Fetching multiple feeds with single SimplePie instance is deprecated since SimplePie 1.9.0, create one SimplePie instance per feed and use SimplePie::merge_items to get a single list of items.', \E_USER_DEPRECATED);770            foreach ($url as $value) {771                $this->multifeed_url[] = $this->registry->call(Misc::class, 'fix_protocol', [$value, 1]);772            }773        } else {774            $this->feed_url = $this->registry->call(Misc::class, 'fix_protocol', [$url, 1]);775            $this->permanent_url = $this->feed_url;776        }777    }