Replace README Gist with CodeSandbox Example

README.md

@@ -128,53 +128,8 @@ To specify how the actions transform the state tree, you write pure *reducers*.
 
 That's it!
 
-```js
-import { createStore } from 'redux'
-
-/**
- * This is a reducer, a pure function with (state, action) => state signature.
- * It describes how an action transforms the state into the next state.
- *
- * The shape of the state is up to you: it can be a primitive, an array, an object,
- * or even an Immutable.js data structure. The only important part is that you should
- * not mutate the state object, but return a new object if the state changes.
- *
- * In this example, we use a `switch` statement and strings, but you can use a helper that
- * follows a different convention (such as function maps) if it makes sense for your
- * project.
- */
-function counter(state = 0, action) {
-  switch (action.type) {
-  case 'INCREMENT':
-    return state + 1
-  case 'DECREMENT':
-    return state - 1
-  default:
-    return state
-  }
-}
-
-// Create a Redux store holding the state of your app.
-// Its API is { subscribe, dispatch, getState }.
-let store = createStore(counter)
-
-// You can use subscribe() to update the UI in response to state changes.
-// Normally you'd use a view binding library (e.g. React Redux) rather than subscribe() directly.
-// However it can also be handy to persist the current state in the localStorage.
-
-store.subscribe(() =>
-  console.log(store.getState())
-)
-
-// The only way to mutate the internal state is to dispatch an action.
-// The actions can be serialized, logged or stored and later replayed.
-store.dispatch({ type: 'INCREMENT' })
-// 1
-store.dispatch({ type: 'INCREMENT' })
-// 2
-store.dispatch({ type: 'DECREMENT' })
-// 1
-```
+<iframe src="https://codesandbox.io/embed/zqq52wqj5p?hidenavigation=1&view=split&previewwindow=console&verticallayout=1&fontsize=12&runonclick=0&codemirror=1&editorsize=75" style="width:100%; height:800px; border:0; border-radius: 4px; overflow:hidden;" sandbox="allow-modals allow-forms allow-popups allow-scripts allow-same-origin"></iframe>
+
 
 Instead of mutating the state directly, you specify the mutations you want to happen with plain objects called *actions*. Then you write a special function called a *reducer* to decide how every action transforms the entire application's state.