text: export class MixinBuilder {
      constructor(superclass) {
          this.superclass = superclass;
      }
  
      with(...mixins) {
          return mixins.reduce((c, mixin) => mixin(c), this.superclass);
      }
  }
  
  export const mix = superclass => new MixinBuilder(superclass);
  
  export default mix;
  