export declare enum Destination {
    Context = 1,
    Content = 2,
    Background = 4,
    Passthrough = 7
}
export declare function isContext(dst: number | Destination): boolean;
export declare function isContent(dst: number | Destination): boolean;
export declare function isBackground(dst: number | Destination): boolean;
export declare function isPassthrough(dst: number | Destination): boolean;
export declare function isWorker(dst: number | Destination): boolean;
export declare function getWorkerId(dst: number | Destination): number;