Run results for: Measure iterations1

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 YaBrowser/24.4.0.0 Safari/537.36

Browser: Yandex Browser 24

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Loop with conditions	49380.6 Ops/sec
Iterator	60712.5 Ops/sec
Generator	64019.7 Ops/sec
.forEach	49096.4 Ops/sec

Script Preparation code:

function filter(iterable, predicate) {
    const iter = iterable[Symbol.iterator]();
    
    return {
        [Symbol.iterator]() {
            return this;
        },
        next() {
            let result;
          
          	while (
              !(result = iter.next()).done &&
              !predicate(result.value)
            );
          
          	return result;
        }
    };
}

function* filterGenerator(iterable, predicate){
    for (const value of iterable) {
        if (predicate(value)) {
            yield value;
        }
    }
}

var arr = Array(100).fill(0).map((_, i) => i + 1);
var predicate = (x) => x % 3 === 0 && x % 5 === 0;

Tests:

Loop with conditions
for (const value of arr) { if (predicate(value)) { console.log('foobar'); } }
Iterator
for (const value of filter(arr, predicate)) { console.log('foobar'); }
Generator
for (const value of filterGenerator(arr, predicate)) { console.log('foobar'); }
.forEach
arr.forEach((x) => predicate(x) && console.log('foobar'));

Run results for: Measure iterations1

Loop with conditions

Iterator

Generator

.forEach