PHP致命错误：无法将词法变量$EventName用作中的参数名

public function once($eventName, callable $listener, $priority = 0) {
    $onceListener = function (
        EventInterface $event,
        $eventName
    ) use (&$onceListener, $eventName, $listener, $priority) {
        $this->removeListener($eventName, $onceListener);
        $listener($event, $eventName, $this);
    };

    $this->on($eventName, $onceListener, $priority);
}

$ composer update guzzlehttp/guzzle

Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 0 installs, 1 update, 0 removals
  - Updating guzzlehttp/guzzle (5.3.0 => 5.3.4): Downloading (100%)
Writing lock file
Generating autoload files