You want an object whose `for...of` can be iterated MULTIPLE times independently. Which `Symbol.iterator` design achieves this?
const range = {
from: 1,
to: 3,
[Symbol.iterator]() {
let current = this.from;
const last = this.to;
return {
next() {
return current <= last
? { value: current++, done: false }
: { value: undefined, done: true };
}
};
}
};