Mimic Python range() for JS

range.js

// Mimic Python range:
// [...range(10)] → [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
// [...range(3, 6)] → [3, 4, 5]
// [...range(3, 20, 2)] → [3, 5, 7, 9, 11, 13, 15, 17, 19]
// for (const i of range(1, 6)) console.log(i);
function* range(from, upTo, step = 1) {
    if (upTo == undefined) {
        upTo = from;
        from = 0;
    }
    while (from < upTo) {
        yield from;
        from += step;
    }
}