stateful functions - generating unique id for objects and iterating collections

iterator.js

(function () {
  function iterator(collection) {
    var index = 0;
    var length = collection.length;

    function next() {
      var item = collection[index++];
      return item;
    }

    function hasNext() {
      return index < length;
    }

    return {
      next: next,
      hasNext: hasNext
    };
  }

  if (typeof Tools == "object") {
    Tools.iterator = iterator;
  }
}());

tools.js

var Tools = {};

uid.js

(function () {
  var id = 0;

  function uid(object) {
    if (typeof object.__uid != "number") {
      object.__uid = id++;
    }

    return object.__uid;
  }

  if (typeof Tools == "object") {
    Tools.uid = uid;
  }
}());