diff --git a/snippets/Timer.md b/snippets/Timer.md
index 990ce0a54..5e25334ef 100644
--- a/snippets/Timer.md
+++ b/snippets/Timer.md
@@ -20,7 +20,7 @@ class Timer extends Component {
 		this.reset()
 		this.interval = setInterval(() => {
 			if (this.state.timer < this.props.time) {
-				this.setState({timer: this.state.timer + 1})
+				this.setState(({ timer }) => ({timer: timer + 1}))
 			}else{
 				clearInterval(this.interval)
 			}
@@ -46,4 +46,4 @@ class Timer extends Component {
 
 ```jsx
 ReactDOM.render(<Timer time={5} interval={1000} />, document.getElementById('root'));
-```
\ No newline at end of file
+```