Object is possibly 'null' for regex

I am able to solve this question using non-null assertion operator ! as below

const body = /<body.*?>([\s\S]*)<\/body>/.exec(html)![1];

If you don't want to use the ! operator, one other option could be to use the optional operator ? and use a default value.

const body = /<body.*?>([\s\S]*)<\/body>/.exec(html)?[1] ?? '';