Revert "Add hooks version"

This reverts commit c9d1d1a898.

snippets/PasswordRevealer.md

@@ -2,8 +2,6 @@
 
 Renders a password input field with a reveal button.
 
-#### Class version
-
 Initially set `state.shown` to `false` to ensure that the password is not shown by default.
 Create a method, `toggleShown`, which uses `Component.prototype.setState` to change the input's state from shown to hidden and vice versa, bind it to the component's context.
 In the`render()` method, use a`<div>` to wrap both the`<input>` and the `<button>` element that toggles the type of the input field.
@@ -38,40 +36,9 @@ class PasswordRevealer extends React.Component {
 ```
 
 ```jsx
-ReactDOM.render(
+ReactDOM.render(<PasswordRevealer />, document.getElementById('root'));
-  <PasswordRevealer />,
-  document.getElementById('root')
-);
 ```
 
-#### Function version
-
-Initialize a state variable `shown` to denote whether or not the password is revealed. Set its initial value to `false`.
-In the `render()` method, return a `<div>` element wrapping the `<input>` element which holds the password and the `<button>` element which reveals or hides it. Bind the button's `onClick` event to the `setShown` function that switches the state variable `shown`'s value from `true` to `false` and vice versa.
-
-```jsx
-function PasswordRevealer() {
-  const [shown, setShown] = useState(false);
-
-  return (
-    <div>
-      <input type={shown ? 'text' : 'password'} />
-      <button onClick={() => setShown(!shown)}>
-        {shown ? 'Hide' : 'Show'}
-      </button>
-    </div>
-  )
-}
-```
-
-```jsx
-ReactDOM.render(
-  <PasswordRevealer />,
-  document.getElementById('root')
-);
-```
-
-
 <!--tags: input,state,class -->
 
 <!--expertise: 0 -->