Run results for: forEach vs manual

Run details:

User agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36

Browser: Chrome 53

Operating system: Windows 7

Device Platform: Other

Date tested: 8 years ago

Script Preparation code:

let items = [];

for (let i = 0; i < 100; i++) {
	items.push({
		something: i
	});
}
window.items = items;

Tests:

forEach
let items = window.items; let theThing; items.forEach(i => { let item = i.something; if (theThing || i === 3) { theThing = i + 3; } }); return theThing;
Cache len
let items = window.items; let theThing; let len = items.length; for (let i = 0; i < len; i++) { let item = items[i].something; if (theThing || item === 3) { theThing = item + 3; } } return theThing;
No cache len
let items = window.items; let theThing; for (let i = 0; i < items.length; i++) { let item = items[i]; if (theThing || item === 3) { theThing = item + 3; } } return theThing;