Run results for: Array filter vs. for loop - with for in 2

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 13_2_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.3 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 13

Operating system: iOS 13.2.3

Device Platform: Mobile

Date tested: 4 years ago

Test name	Executions per second
Filter	3975156.0 Ops/sec
For	493023.4 Ops/sec
For 2	495922.1 Ops/sec
For in	509526.1 Ops/sec

Script Preparation code:

var arr = [1,2,3,4,5,6,7,8,9,0], farr, i,len;

Tests:

Filter
farr = arr.filter(function(item) { return (item>4); });
For
for (i=0,len=arr.length;i<len;i++) { if (arr[i]<5) continue; farr.push(arr[i]); }
For 2
for (i=0,len=arr.length;i<len;i++) { if (arr[i]>4) farr.push(arr[i]); }
For in
for (i in arr) { if (arr[i]>4) farr.push(arr[i]); }

Run results for: Array filter vs. for loop - with for in 2

This version declares i once before

Filter

For

For 2

For in