Benchmark: Array forEach callback function as a parameter vs as a predefined variable + compared to using callback parameters vs without + for..of, for..in, for loop

Array forEach callback function as a parameter vs as a predefined variable + compared to using callback parameters vs without + for..of, for..in, for loop (version: 1)

Script Preparation code:

var array = new Array(100);

var fn = function(el, idx, arr) {
  el;
}

Tests:

Array forEach, callback function provided as an argument, ignoring most callback arguments
array.forEach(function(_el, idx, _arr) { array[idx]; });
Array forEach, callback function provided as an argument
array.forEach(function(el, idx, arr) { el; });
Array forEach, callback function provided as a predefined variable
array.forEach(fn);
for..of
for (const i of array) { array[i]; }
for..in
for (var i in array) { array[i]; }
for loop
for (var i = 0; i < array.length; i++) { array[i]; }

Rendered benchmark preparation results:

Previous results

Test case name	Result
Array forEach, callback function provided as an argument, ignoring most callback arguments
Array forEach, callback function provided as an argument
Array forEach, callback function provided as a predefined variable
for..of
for..in
for loop

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Linux

Array forEach, callback function provided as an argument, ignoring most callback arguments

5.6M/s

Array forEach, callback function provided as an argument

5.6M/s

for..in

4.7M/s

for loop

3.4M/s

Array forEach, callback function provided as a predefined variable

3.4M/s

for..of

733K/s

View exact numbers

Test name	Executions per second
✓ Array forEach, callback function provided as an argument, ignoring most callback arguments	5,601,961 Ops/sec
Array forEach, callback function provided as an argument	5,600,143 Ops/sec
for..in	4,747,800 Ops/sec
for loop	3,430,163 Ops/sec
Array forEach, callback function provided as a predefined variable	3,423,975 Ops/sec
for..of	733,335 Ops/sec