Benchmark: Plain object, for vs for in vs for of

Script Preparation code:

var a = {
    first: 'john',
    last: 'smith',
    address: {
        street: 'street street'
    }
};

var b = {
    first: 'j',
    last: 's'
};

Tests:

for loop
const props = Object.keys(a); const length = props.length; let hasNewKey = false; for (let i = 0; i < length; i++) { const key = props[i]; if (!(key in b)) { hasNewkey = true; } }
for of
const props = Object.keys(a); let hasNewKey = false; for (const key of props) { if (!(key in b)) { hasNewkey = true; } }
for in
let hasNewKey = false; for (const key in a) { if (!(key in b)) { hasNewkey = true; } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for loop
for of
for in

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/101.0.4951.58 Mobile/15E148 Safari/604.1

Browser/OS: Chrome Mobile iOS 101 on iOS 15.3

View result in a separate tab

Test name	Executions per second
for loop	1950828.0 Ops/sec
for of	2000453.0 Ops/sec
for in	2010761.0 Ops/sec

Plain object, for vs for in vs for of (version: 0)

Comparing performance of: for loop vs for of vs for in

Created: one year ago by: Guest

Jump to the latest result

for loop

for of

for in

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A