export declare class ObjectUtils {
    /**
     * Copy the values of all of the enumerable own properties from one or more source objects to a
     * target object. Returns the target object.
     * @param target The target object to copy to.
     * @param source The source object from which to copy properties.
     */
    static assign<T, U>(target: T, source: U): T & U;
    /**
     * Copy the values of all of the enumerable own properties from one or more source objects to a
     * target object. Returns the target object.
     * @param target The target object to copy to.
     * @param source1 The first source object from which to copy properties.
     * @param source2 The second source object from which to copy properties.
     */
    static assign<T, U, V>(target: T, source1: U, source2: V): T & U & V;
    /**
     * Copy the values of all of the enumerable own properties from one or more source objects to a
     * target object. Returns the target object.
     * @param target The target object to copy to.
     * @param source1 The first source object from which to copy properties.
     * @param source2 The second source object from which to copy properties.
     * @param source3 The third source object from which to copy properties.
     */
    static assign<T, U, V, W>(target: T, source1: U, source2: V, source3: W): T & U & V & W;
}