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              <script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.6.0/moment.min.js"></script>
<script type="text/jsx">
/** @jsx React.DOM */
'use strict';

// A simple class to capture a one-way value transform function.
var ValueTransformer = function (transform) {
  this.func = (typeof transform === 'function') 
  ? transform 
  : function (value) { return value.toString ? value.toString() : value; }

// Transforms the input value according to the pre-defined transform function
ValueTransformer.prototype.getTransformedValue = function (value) {
  return this.func.call(null, value);

// Define some value transforms
// ----------------------------
var timeTransform = new ValueTransformer(function (date) {
  return moment(date).format('h:mm:ss a');

var militaryTimeTransform = new ValueTransformer(function (date) {
  return moment(date).format('HH:mm:ss');

var microTimeTransform = new ValueTransformer(function (date) {
  return moment(date).format('HH:mm:ss:SSS');

var myCustomTransform = new ValueTransformer(function (date) {
  return <span>

// Define our Clock component
// --------------------------
var Clock = React.createClass({
  getDefaultProps: function () {
    return {
      date: new Date(),
      dateTransform: new ValueTransformer()
  getTime: function () {
    return this.props.dateTransform.getTransformedValue(this.props.date);
  render: function () {
    return <span>{this.getTime()}</span>; 

// Render our clocks, saving a ref to each
// ---------------------------------------
var clocks = {
  rawDate: React.renderComponent(
    <Clock />, 
  clock12: React.renderComponent(
    <Clock dateTransform={timeTransform} />, 
  clock24: React.renderComponent(
    <Clock dateTransform={militaryTimeTransform} />, 
  mirotime: React.renderComponent(
    <Clock dateTransform={microTimeTransform} />, 
  customClock: React.renderComponent(
    <Clock dateTransform={myCustomTransform} />, 

// Update the clocks as time passes 
// --------------------------------
window.setInterval(function () {
  for(var prop in clocks) {
    if(clocks.hasOwnProperty(prop)) {
      var clock = clocks[prop];
        date: new Date()
}, 10);

  <dt>Raw Date</dt>
  <dd id="raw-date"></dd>
  <dt>12 Hour Time</dt>
  <dd id="time-12hr"></dd>
  <dt>24 Hour Time</dt>
  <dd id="time-24hr"></dd>
  <dd id="time-microtime"></dd>
  <dd id="time-custom"></dd>

              dl {
  margin: 1em;

dt {
  color: #999;

dd {
  margin: 1em;
  font-family: monospace;
  font-size: 1.2em;
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