Extension

More

note

All files prefixed with an underscore (_) under the docs directory are treated as "partial" pages and will be ignored by default.

Customize Title

All files prefixed with an underscore (_) under the docs directory are treated as "partial" pages and will be ignored by default.

info

Check the for an exhaustive list of options.

tip

Tips

warning

Warning

danger

Danger

Markdown is declarative

Some content

Diagram

http://localhost:3000

Live Editor

function Clock(props) {
  const [date, setDate] = useState(new Date());
  useEffect(() => {
    const timerID = setInterval(() => tick(), 1000);

    return function cleanup() {
      clearInterval(timerID);
    };
  });

  function tick() {
    setDate(new Date());
  }

  return (
    <div>
      <h2>It is {date.toLocaleTimeString()}.</h2>
    </div>
  );
}

Result

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You can declare custom magic comments through theme config. For example, you can register another magic comment that adds a code-block-error-line class name:

docusaurus.config.js

export default {
  themeConfig: {
    prism: {
      magicComments: [
        // Remember to extend the default highlight class name as well!
        {
          className: 'theme-code-block-highlighted-line',
          line: 'highlight-next-line',
          block: {start: 'highlight-start', end: 'highlight-end'},
        },
        {
          className: 'code-block-error-line',
          line: 'This will error',
        },
      ],
    },
  },
};

src/css/custom.css

.code-block-error-line {
  background-color: #ff000020;
  display: block;
  margin: 0 calc(-1 * var(--ifm-pre-padding));
  padding: 0 var(--ifm-pre-padding);
  border-left: 3px solid #ff000080;
}

myDoc.md

In JavaScript, trying to access properties on `null` will error.

```js
const name = null;
// This will error
console.log(name.toUpperCase());
// Uncaught TypeError: Cannot read properties of null (reading 'toUpperCase')
```