← You've been doing Set math by hand. JavaScript finally shipped `.union()`, `.intersection()`, and friends.Quiz

Set methods: union, intersection, difference, symmetricDifference

ES2025 gave Set seven new methods — four that return a new set and three boolean predicates. Test whether you've got the mutation rules, the set-like contract, and a couple of genuinely sharp edge cases straight.

questions6

pass mark70%

resultsat the end

No account needed. Answer all 6 questions, then see your score with every answer explained and a reference to the spec or MDN — pass and you can claim a certificate.