layer-cake without generators

simpler-layer-cake.js

// https://github.com/Agoric/layer-cake without generators

const {
  create: objCreate,
  getOwnPropertyDescriptors: gopds,
  defineProperties,
  prototype: objPrototype,
  freeze,
} = Object;

function makeCakeMaker(combineLayers) {
  return function makeCake(layerGens) {
    let self = {};
    layerGens.forEach(layerGen => {
      const supr = {};
      const layer = layerGen(self, supr);
      Object.assign(supr, self);
      combineLayers(self, layer);
    });
    return self;
  };
}

const makeClassCake = makeCakeMaker((upper = {}, lower = {}) =>
  Object.assign(upper, lower)
);

function BasePointLayer(x, y) {
  return (self) => ({
      getX() { return x; },
      getY() { return y; },
      toString() { return `<${self.getX()},${self.getY()}>`; },  
  });
}

function WobblyPointLayer(wobble) {
  return (_self, supr) => ({
    getX() { return supr.getX() + wobble++; }
  });
}

function makeWobblyPoint(x, y, wobble) {
  return makeClassCake([BasePointLayer(x, y), WobblyPointLayer(wobble)]);
}

let point = makeWobblyPoint(1,1,1);
console.log(point.toString()); // <2,1>