/**
 * To support the `for await` pattern of `Connection` when receiving messages, we need to have some kind of queue
 * structure that will handle incoming packets. This isn't meant to use publicly, but could be if need be.
 */
export default class AsyncQueue<T> {
    /**
     * The promise used to determine when a value is inserted into the queue.
     */
    private _next;
    /**
     * If `_next` has already been resolved (i.e. from the `_buffer`), this will be true. This is used in `push` to
     * determine if `_resolve` should be called, or if the value should be pushed into `_buffer`.
     */
    private _prepared;
    /**
     * A function that will resolve the `_next` promise. This is typically called upon when a method is `push`ed into
     * the queue.
     */
    private _resolve;
    /**
     * The rejection callback incase the queue needs to be cancelled.
     */
    private _reject;
    /**
     * A buffer that will have extra unhandled values pushed into it.
     */
    private _buffer;
    constructor();
    push(value: T): void;
    end(error: Error): void;
    next(): Promise<T | undefined>;
}