/**
 * The Socket.IO typedefs leave a lot to be desired,
 * so we augment them a bit here for improved precision
 * and coverage.
 */
declare namespace SocketIO {
    /**
     * Lange: I'm actually upset at how poorly documented this part of Socket.IO is lmao
     */
    type NextFunction = (err?: NodeJS.ErrnoException) => void;
    type Acknowledgement = (err?: NodeJS.ErrnoException, data?: any) => void;
}