export declare const Mix: (superclass: any) => MixinBuilder;
/**
 * Creates a new class that extends with multiple mixins.
 *
 * @mixin
 * @example
 * class MyClass extends Mix(HTMLElement).with(Mixin, OtherMixin) {...}
 * @param {Function} superclass - The base class to extend upon.
 */
export declare class MixinBuilder {
    superclass: any;
    constructor(superclass: any);
    with(...mixins: any[]): any;
}