Run results for: for vs for in vs for of vs forEach - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.36

Browser: Chrome 99

Operating system: Linux

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
forEach	344844.6 Ops/sec
for of	558117.6 Ops/sec
for in	3980.7 Ops/sec
for	2965.6 Ops/sec

Script Preparation code:

var data = [... new Array(1000)].map((x,i) => i);

Tests:

forEach
let result = 0; data.forEach(x => { result = x; });
for of
let result = 0; for (let x of data) { result = x; }
for in
let result = 0; for (let i in data) { result = data[i]; }
for
let result = 0; for (let i = 0; i < data.length; i++) { result = data[i]; }

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