CodeBlocks

As you go to the next slide this code block will first highlight lines 1-2, then line 3, then finally line 4.

Note: the js indicates that this code should be highlighted as javascript

```js [1-2|3|4]
let a = 1;
let b = 2;
let c = x => 1 + 2 + x;
c(3);
```

For the full documentation about what you can do with code blocks see: https://revealjs.com/code/