operator-overloading.js

class Vec {
  #x;
  #y;
  #z;
  
  constructor(x, y, z) {
    this.#x = x;
    this.#y = y;
    this.#z = z;
  }
  
  static #operators = {
    "+"(a, b) { return new Vec(a.#x + b.#x, a.#y + b.#y, a.#z + b.#z); }
    "-"(a, b) { return new Vec(a.#x - b.#x, a.#y - b.#y, a.#z - b.#z); }
  };

  get [Symbol.operators]() { return Vec.#operators }
}