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    <h1>React Primer  3 - Counter in Redux
    <p>In this example, we will expose the internal counter value to the external world with redux:</p>
    <p>We take a shortcut by using the global variable `store`:</p>
    <div id="app" />


                body {
  padding: 2em;
#app {
  font-size: 3em;
  .button {
    border-radius: 4px;
    border-color: #DFC235;
    text-shadow: 0 1px 0 #FCFC85;
    background-color: #f8f777;
    background: linear-gradient(to bottom, #f8f777, #dfc235);
    font-size: .8em;
    padding: 10px 18px;
    margin-left: 20px


                const initState = {
  counter: 10,
  text: 'foo',

// reducers
const rootReducer = (state, action) => {
  switch(action.type) {
    case 'INCR':
      return {...state, counter: state.counter + 1};
    case 'DECR':
      return {...state, counter: state.counter - 1};
      return state;

// store stores the ultimate state, and we can 
// drive the state machine by dispatch(action)
const store = Redux.createStore(
  rootReducer, initState

// component:
const Counter = ({counter}) => {
  return (
        onClick={(e) => store.dispatch({type: 'INCR'})}
        onClick={(e) => store.dispatch({type: 'DECR'})}

const mapStateToProps = (state) => {
  return {
    counter: state.counter,

// App is a smart container!
const App = ReactRedux.connect(

// index.js
  <ReactRedux.Provider store={store}>
    <App />