Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.9999.0 Safari/537.36
Chrome 102
Mac OS X 10.15.7
Desktop
2 years ago
Test name Executions per second
concat.apply 1130603.0 Ops/sec
flat 8192.7 Ops/sec
Script Preparation code:
x
 
var array1 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array2 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array3 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array4 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var array5 = Array(400).fill().map(() => Math.round(Math.random() * 40));
var allArrays = [array1, array2, array3, array4, array5];
Tests:
  • concat.apply

     
    var others = [].concat.apply([], allArrays);
  • flat

     
    var others = allArrays.flat()