array intersection, diff, symmetrical difference

array-intersection-diff-bi-diff.ts

const a = [1,2,3]
const b = [1,4,5]

// using find instead includes
const inter = a.filter(x => b.find(x1 => x1 == x));
const diff = a.filter(x => !b.find(x1 => x1 == x));
const simtricDiff = a.filter(x => !b.find(x1 => x1 == x)).concat(b.filter(x => !a.find(x1 => x1 == x)));

inter // [ 1 ]

diff // [ 2, 3 ]

simetricDiff // [ 2, 3, 4, 5 ]