es5_getter_setter.js

window.Person = {
  warnChangeInAttribute: function(attribute, pastValue, value) {
    console.log(attribute + " changed from " + pastValue + " to " + value);
  }
};

Object.defineProperty(window.Person, "name", {
  get: function() {
    return this.nameValue;
  },
  set: function(name) {
    this.namePastValue = this.nameValue;
    this.nameValue = name;
    this.warnChangeInAttribute("name", this.namePastValue, this.nameValue);
  }
});