const obj = { foo: 1 };
obj.bar = 2;
[...[...'...']].length
typeof (new (class F extends (String, Array) { })).substring
(function() {
if (false) {
let f = { g() => 1 };
}
return typeof f;
})()
let a = 12, b = 3;
[a, b] = [b, a];