function* range(start, stop) {
    if (typeof stop !== 'number') {
        stop = start;
        start = 0;
    }
    let current = start;
    while (current < stop) {
        yield current;
        current++;
    }
}

function* generatorFilter(sequence, predicate) {
    for (const element of sequence) {
        if (predicate(element)) {
            yield element;
        }
    }
}

function iteratorFilter(sequence, predicate) {
return {
        [Symbol.iterator]() {
            const itr = sequence[Symbol.iterator]();
            return {
                next() {
                    let current = itr.next();
                    while (!current.done &&
                        !predicate(current.value)) {
                        current = itr.next();
                    }
                    return current;
                },
            };
        },
    };
}

function filterCallback(sequence, predicate, callback) {
	for (const e of sequence) {
		if (predicate(e)) {
			callback(e);
		}
	}
}

const data = Array.from(range(100000));
const isEven = (n) => n % 2 === 0;