.js

    createPropertyAccessor: function(name, ignoreWrites) {
      var proto = this.prototype;
      var privateName = name + '_';
      var privateObservable  = name + 'Observable_';
 
      Object.defineProperty(proto, name, {
        get: function() {
          var observable = this[privateObservable];
          if (observable)
            observable.deliver();
 
          return this[privateName];
        },
        set: function(value) {
          if (ignoreWrites) {
            return;
          }
 
          var observable = this[privateObservable];
          if (observable) {
            observable.setValue(value);
            return;
          }
 
          var oldValue = this[privateName];
          this[privateName] = value;
          this.emitPropertyChangeRecord(name, value, oldValue);
        },
        configurable: true
      });