# @extends
## #examples
## Example: diagonal line
The following example uses a while loop to make a diagonal line on the LED screen (points `0, 0`, `1, 1`, `2, 2`, `3, 3`, `4, 4`).
```blocks
input.onButtonPressed(Button.A, () => {
let index = 4;
while(index >= 0) {
led.plot(index, index);
index--;
}
})
```
