Mixins in ES6

I had been looking for a good way to do mixins in ES6.

Looks like I finally found one.

http://raganwald.com/2015/06/10/mixins.html

Essentially,

create the mixin as a const

Use Object.assign to add the properties to the Class

const BookCollector = {
  addToCollection (name) {
    this.collection().push(name);
    return this;
  },
  collection () {
    return this._collected_books || (this._collected_books = []);
  }
};

class Person {
  constructor (first, last) {
    this.rename(first, last);
  }
  fullName () {
    return this.firstName + " " + this.lastName;
  }
  rename (first, last) {
    this.firstName = first;
    this.lastName = last;
    return this;
  }
};

Object.assign(Person.prototype, BookCollector);

(I am copying and pasting this for personal reference in case the original site link goes down).