// this causes an unhandled rejection after sleep(1) expires because keepalive is not set
sleep(1).then(() => ocx.println('printing later!'));
// this does not cause an unhandled rejection after sleep(1) expires because keepalive is set
keepalive();
sleep(1).then(() => ocx.println('printing later!'));
// this does not cause an unhandled rejection after sleep(1) expires because the error is handled
sleep(1).then(() => ocx.println('printing later!')).catch(render_error);
### the javascript code causes an unhandled rejection after sleep(1) expires because keepalive is not set
*... with math:*
$$
x = \frac{-b \pm \sqrt{b^2 - 4 a c}}{2 a}
$$
*... with code:*
```!$ javascript
sleep(1).then(() => ocx.println('printing later!'));
```
### the javascript code does not cause an unhandled rejection after sleep(1) expires because keepalive is set
*... with math:*
$$
x = \frac{-b \pm \sqrt{b^2 - 4 a c}}{2 a}
$$
*... with code:*
```!$ javascript
keepalive();
sleep(1).then(() => ocx.println('printing later!'));
```
### the javascript code does not cause an unhandled rejection after sleep(1) expires because the error is handled
*... with math:*
$$
x = \frac{-b \pm \sqrt{b^2 - 4 a c}}{2 a}
$$
*... with code:*
```!$ javascript
sleep(1).then(() => ocx.println('printing later!')).catch(render_error);
```