Aerys\Router::bootRouteTarget PHP Method

    private function bootRouteTarget($actions) : array
    {
        $middlewares = [];
        $applications = [];
        $booted = [];
        $monitors = [];
        foreach ($actions as $key => $action) {
            if ($action instanceof Bootable) {
                /* don't ever boot a Bootable twice */
                $hash = spl_object_hash($action);
                if (!array_key_exists($hash, $booted)) {
                    $booted[$hash] = ($this->bootLoader)($action);
                }
                $action = $booted[$hash];
            } elseif (is_array($action) && $action[0] instanceof Bootable) {
                /* don't ever boot a Bootable twice */
                $hash = spl_object_hash($action[0]);
                if (!array_key_exists($hash, $booted)) {
                    $booted[$hash] = ($this->bootLoader)($action[0]);
                }
            }
            if ($action instanceof Middleware) {
                $middlewares[] = [$action, "do"];
            } elseif (is_array($action) && $action[0] instanceof Middleware) {
                $middlewares[] = [$action[0], "do"];
            }
            if ($action instanceof Monitor) {
                $monitors[get_class($action)][] = $action;
            } elseif (is_array($action) && $action[0] instanceof Monitor) {
                $monitors[get_class($action[0])][] = $action[0];
            }
            if (is_callable($action)) {
                $applications[] = $action;
            }
        }
        if (empty($applications[1])) {
            if (empty($applications[0])) {
                // in order to specify only middlewares (in combination with e.g. a fallback handler)
                return [[function () {
                }, $middlewares], $monitors];
            } else {
                return [[$applications[0], $middlewares], $monitors];
            }
        }
        return [[static function (Request $request, Response $response, array $args) use($applications) {
            foreach ($applications as $application) {
                $result = $application($request, $response, $args);
                if ($result instanceof \Generator) {
                    yield from $result;
                }
                if ($response->state() & Response::STARTED) {
                    return;
                }
            }
        }, $middlewares], $monitors];
    }