export type WebSocketSupportedPayload = string | ArrayBufferLike | Blob | ArrayBufferView;
export type PrepMessage<T> = T | Promise<T> | (() => T | Promise<T>);
/**
 * Helper which returns a method that sends data over the given {@link WebSocket}, including queuing until it is connected.
 * This method returns `true` if the data was sent, or ever has a chance of being sent (i.e., not closed/closing).
 *
 * The passed message can be a `Promise`, or a function which returns a `Promise`.
 *
 * The data is sent without being transformed (i.e., no {@link JSON.stringify}), but you can pass this as the second arg if it's important to you.
 */
export declare function socketQueueSend<T = WebSocketSupportedPayload>(socket: WebSocket | Promise<WebSocket>, transformMessage?: (m: T) => WebSocketSupportedPayload | undefined): (message: PrepMessage<T>) => boolean;
export type SocketConnectArg = {
    /**
     * Signal that, if specified, closes the {@link WebSocket} when aborted.
     */
    signal?: AbortSignal;
    /**
     * The delay to wait for before opening the socket.
     */
    delay?: number;
    /**
     * Any protocols (second arg of {@link WebSocket} constructor).
     */
    protocols?: string | string[];
    /**
     * If specified, automatically added as the "message" handler.
     */
    message?: (e: MessageEvent) => void;
};
/**
 * Helper which prepares a {@link WebSocket} in a {@link Promise} that only resolves when it is ready.
 *
 * Additionally, accepts a {@link AbortSignal} which can be used to shut down the socket early.
 * This will cause the method to throw if already aborted.
 */
export declare function socketConnect(url: string, opts?: SocketConnectArg): Promise<WebSocket>;