JavaScript · Regular expressions

Sticky flag

The y flag anchors each match at lastIndex, which suits tokenisers.

javascriptRunnable example javascript course

Syntax

/pattern/y

Example

Try it

const re = /\w+/y;
re.lastIndex = 2;
console.log(re.exec("ab cd"));

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