JavaScript · Regular expressions

Capture groups

Parenthesised groups capture parts of a match by number.

javascriptRunnable example javascript course

Syntax

/(\w+)@(\w+)/

Example

Try it

const [, user, host] = /(\w+)@(\w+)/.exec("ada@example") || [];
console.log(user, host);

Reference pages are the quick answer. The course explains the why, shows the full example and ends with a challenge.