// Parameter default values work in arrow functions load(libdir + "asserts.js"); var f = (a=1, b=2, ...rest) => [a, b, rest]; assertDeepEq(f(), [1, 2, []]); assertDeepEq(f(0, 0), [0, 0, []]); assertDeepEq(f(0, 1, 1, 2, 3, 5), [0, 1, [1, 2, 3, 5]]);