export declare function checkObservable(x: any): void;
export declare function checkProperty(x: any): void;
export declare function checkEventStream(x: any): void;
export declare function checkNaturalInt(x: any): void;
export declare function checkPositiveInt(x: any): void;
export declare function checkFunction(x: any): void;
export declare function checkArray(x: any): void;
export declare function checkFunctionOrProperty(x: any): void;