30-seconds-of-code/snippets/intersects.md

title, tags, author, cover, firstSeen

title	tags	author	cover	firstSeen
Check if two arrays intersect	array	chalarangelo	blog_images/interior-5.jpg	2023-02-17T05:00:00-04:00

Determines if two arrays have a common item.

• Create a Set from b to get the unique values in b.
• Use Array.prototype.some() on a to check if any of its values are contained in b, using Set.prototype.has().

const intersects = (a, b) => {
  const s = new Set(b);
  return [...new Set(a)].some(x => s.has(x));
};

intersects(['a', 'b'], ['b', 'c']); // true
intersects(['a', 'b'], ['c', 'd']); // false