The has() method of the Highlight interface returns a boolean indicating whether an AbstractRange object exists in a Highlight object or not.
Highlight is a Set-like object, so this is similar to using Set.has().
has(range)rangeThe AbstractRange object to test for presence in the Highlight object.
Returns true if the specified range exists in the Highlight object; otherwise false.
The code snippet below creates two ranges, and a highlight object that contains one of them. The code then uses the has() method to check whether each range exists in the highlight:
const range1 = new Range();
const range2 = new Range();
const myHighlight = new Highlight(range1);
myHighlight.has(range1); // true
myHighlight.has(range2); // false