Self-incrementing, read-only counter property; prototype linking version.

run.js

(function IIFE() {
  'use strict';
  function counter() {
    this.def = 0;
    return (function() {
      return this.def++;
    }).bind(this);
  };
  var obj = {};
  Object.defineProperties(obj, {
    counter: {
      get: new counter,
      enumerable: true
    }
  });
  console.log(obj.counter, obj.counter, obj.counter);
})();