Run results for: Object.values foreach vs Object for-in overhead cost

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:138.0) Gecko/20100101 Firefox/138.0

Browser: Firefox 138

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Call Object.values on each execution

74K/s

Use shared Object.values

42K/s

View exact numbers

Test name	Executions per second
✓ Call Object.values on each execution	73,970 Ops/sec
Use shared Object.values	41,563 Ops/sec

Script Preparation code:

var myObj = {};
for (var i = 0; i < 1000; i++) {
    myObj['val' + i] = 'val' + i;
}
//var myObjValues = Object.values(myObj);

Tests:

Call Object.values on each execution
var objValues = Object.values(myObj); var myStr = ''; objValues.forEach(el => myStr += el);
Use shared Object.values
var myStr = ''; for (const o in myObj) { myStr += myObj[o]; }