old_contents: (function () {
      "use strict";
      var Tornado = function(cities,windGust,type) {
          this.cities = cities;
          this.windGust = windGust;
          this.type = type;
      };
  
      var cities = [["New York", 1234], ["California", 234]];
      var katrina = new Tornado(cities, '120mph', 'F12');
  
      console.log("Tornado "+ katrina);
  
      Tornado.prototype.valueOf = function () {
          var sum = 0;
          for(var i=0; i <= this.cities.length-1; i++) {
              console.log("..."+ cities);
              sum += this.cities[i][1];
          }
          return sum;
      }
  
      var twister = new Tornado(cities, '34mph', 'F23');
      cities.push(["London", 2000]);
      console.log("Tornado "+ katrina.valueOf());
      console.log("twister" + twister.constructor);
      console.log("twister" + twister.constructor.prototype);
  
  }());
new_contents: (function () {
      "use strict";
      var Tornado = function(cities,windGust,type) {
          this.cities = cities;
          this.windGust = windGust;
          this.type = type;
      };
  
      var cities = [["New York", 1234], ["California", 234]];
      var katrina = new Tornado(cities, '120mph', 'F12');
  
      console.log("Tornado "+ katrina);
  
      Tornado.prototype.valueOf = function () {
          var sum = 0;
          for(var i=0; i <= this.cities.length-1; i++) {
              console.log("..."+ cities);
              sum += this.cities[i][1];
          }
          return sum;
      };
  
      var twister = new Tornado(cities, '34mph', 'F23');
      cities.push(["London", 2000]);
      console.log("Tornado "+ katrina.valueOf());
      console.log("twister" + twister.constructor);
      console.log("twister" + twister.constructor.prototype);
  
  }());
subject: tidy code