export declare type Data = {
    readonly [key: string]: any;
} | null;
export declare type SubIdentifier = {
    readonly name: string;
    readonly pass: string;
    retries: number;
};
export declare type Listener = (props: {
    source: Window;
    command: string;
    data: Data;
}) => void;
export declare type KillListener = (props: {
    source: Window;
}) => void;
export declare type HandshakeListener = (props: {
    source: Window;
    name: string;
}) => void;
export declare type Unlisten = () => void;