"use strict";

class Box {

    constructor(params = {}) {

        var { x = 0, y = 0, height = 1, width = 1 } = params;

        this.x = x;

        this.y = y;

        this.height = height;

        this.width = width;

    }

}

const b = new Box({ x:3, y: 0, height: 23, width: 1});

console.assert(b.x === 3)

class Box {

  constructor(params = {}){

        this.x = 0;

        this.y = 0;

        this.height = 1;

        this.width = 1;

        Object.assign(this, params);

  }

}

const a = new Box({ x:3, y: 0, height: 23, width: 1});

console.assert(a.x === 3)