gistfile1.js

var ReactiveValue = function(value) {
  var dep = new Deps.Dependency();
  var state = value;
  this.get = function() {
    dep.depend();
    return state;
  }
  this.set = function(newValue) {
    if (state === newValue) return;
    state = newValue;
    dep.changed();
  };
};