Run results for: Switch vs Prepared Object Literal vs Prepared Array vs Prepared Map

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36 Edg/111.0.1661.62

Browser: Chrome 111

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Switch	960429.2 Ops/sec
Object Literal	934744.6 Ops/sec
Array Literal	949273.4 Ops/sec
Map Literal	923623.1 Ops/sec

Script Preparation code:


var arrayLiteral = [
function(){return 'a' + '0' + Math.random(); }
,function(){return 'b' + '1' + Math.random(); }
,function(){return 'c' + '2' + Math.random(); }
,function(){return 'd' + '3' + Math.random(); }
,function(){return 'e' + '4' + Math.random(); }
,function(){return 'f' + '5' + Math.random(); }
,function(){return 'g' + '6' + Math.random(); }
,function(){return 'h' + '7' + Math.random(); }
,function(){return 'i' + '8' + Math.random(); }
,function(){return 'j' + '9' + Math.random(); }
,function(){return 'k' + '10' + Math.random(); }
,function(){return 'l' + '11' + Math.random(); }
,function(){return 'm' + '12' + Math.random(); }
,function(){return 'n' + '13' + Math.random(); }
,function(){return 'o' + '14' + Math.random(); }
,function(){return 'p' + '15' + Math.random(); }
,function(){return 'q' + '16' + Math.random(); }
,function(){return 'r' + '17' + Math.random(); }
,function(){return 's' + '18' + Math.random(); }
,function(){return 't' + '19' + Math.random(); }
,function(){return 'u' + '20' + Math.random(); }
,function(){return 'v' + '21' + Math.random(); }
,function(){return 'w' + '22' + Math.random(); }
,function(){return 'x' + '23' + Math.random(); }
,function(){return 'y' + '24' + Math.random(); }
,function(){return 'z' + '25' + Math.random(); }
,function(){return 'A' + '26' + Math.random(); }
,function(){return 'B' + '27' + Math.random(); }
,function(){return 'C' + '28' + Math.random(); }
,function(){return 'D' + '29' + Math.random(); }
,function(){return 'E' + '30' + Math.random(); }
,function(){return 'F' + '31' + Math.random(); }
,function(){return 'G' + '32' + Math.random(); }
,function(){return 'H' + '33' + Math.random(); }
,function(){return 'I' + '34' + Math.random(); }
,function(){return 'J' + '35' + Math.random(); }
,function(){return 'K' + '36' + Math.random(); }
,function(){return 'L' + '37' + Math.random(); }
,function(){return 'M' + '38' + Math.random(); }
,function(){return 'N' + '39' + Math.random(); }
,function(){return 'O' + '40' + Math.random(); }
,function(){return 'P' + '41' + Math.random(); }
,function(){return 'Q' + '42' + Math.random(); }
,function(){return 'R' + '43' + Math.random(); }
,function(){return 'S' + '44' + Math.random(); }
,function(){return 'T' + '45' + Math.random(); }
,function(){return 'U' + '46' + Math.random(); }
,function(){return 'V' + '47' + Math.random(); }
,function(){return 'W' + '48' + Math.random(); }
,function(){return 'X' + '49' + Math.random(); }
,function(){return 'Y' + '50' + Math.random(); }
,function(){return 'Z' + '51' + Math.random(); }
,function(){return 'a' + '52' + Math.random(); }
,function(){return 'b' + '53' + Math.random(); }
,function(){return 'c' + '54' + Math.random(); }
,function(){return 'd' + '55' + Math.random(); }
,function(){return 'e' + '56' + Math.random(); }
,function(){return 'f' + '57' + Math.random(); }
,function(){return 'g' + '58' + Math.random(); }
,function(){return 'h' + '59' + Math.random(); }
,function(){return 'i' + '60' + Math.random(); }
,function(){return 'j' + '61' + Math.random(); }
,function(){return 'k' + '62' + Math.random(); }
,function(){return 'l' + '63' + Math.random(); }
];
var objLiteral = Object.fromEntries(arrayLiteral.entries());
var map = new Map(arrayLiteral.entries());
function usingSwitch(c) {
  switch (c) {
case 0: 'a' + '0' + Math.random(); break;
case 1: 'b' + '1' + Math.random(); break;
case 2: 'c' + '2' + Math.random(); break;
case 3: 'd' + '3' + Math.random(); break;
case 4: 'e' + '4' + Math.random(); break;
case 5: 'f' + '5' + Math.random(); break;
case 6: 'g' + '6' + Math.random(); break;
case 7: 'h' + '7' + Math.random(); break;
case 8: 'i' + '8' + Math.random(); break;
case 9: 'j' + '9' + Math.random(); break;
case 10: 'k' + '10' + Math.random(); break;
case 11: 'l' + '11' + Math.random(); break;
case 12: 'm' + '12' + Math.random(); break;
case 13: 'n' + '13' + Math.random(); break;
case 14: 'o' + '14' + Math.random(); break;
case 15: 'p' + '15' + Math.random(); break;
case 16: 'q' + '16' + Math.random(); break;
case 17: 'r' + '17' + Math.random(); break;
case 18: 's' + '18' + Math.random(); break;
case 19: 't' + '19' + Math.random(); break;
case 20: 'u' + '20' + Math.random(); break;
case 21: 'v' + '21' + Math.random(); break;
case 22: 'w' + '22' + Math.random(); break;
case 23: 'x' + '23' + Math.random(); break;
case 24: 'y' + '24' + Math.random(); break;
case 25: 'z' + '25' + Math.random(); break;
case 26: 'A' + '26' + Math.random(); break;
case 27: 'B' + '27' + Math.random(); break;
case 28: 'C' + '28' + Math.random(); break;
case 29: 'D' + '29' + Math.random(); break;
case 30: 'E' + '30' + Math.random(); break;
case 31: 'F' + '31' + Math.random(); break;
case 32: 'G' + '32' + Math.random(); break;
case 33: 'H' + '33' + Math.random(); break;
case 34: 'I' + '34' + Math.random(); break;
case 35: 'J' + '35' + Math.random(); break;
case 36: 'K' + '36' + Math.random(); break;
case 37: 'L' + '37' + Math.random(); break;
case 38: 'M' + '38' + Math.random(); break;
case 39: 'N' + '39' + Math.random(); break;
case 40: 'O' + '40' + Math.random(); break;
case 41: 'P' + '41' + Math.random(); break;
case 42: 'Q' + '42' + Math.random(); break;
case 43: 'R' + '43' + Math.random(); break;
case 44: 'S' + '44' + Math.random(); break;
case 45: 'T' + '45' + Math.random(); break;
case 46: 'U' + '46' + Math.random(); break;
case 47: 'V' + '47' + Math.random(); break;
case 48: 'W' + '48' + Math.random(); break;
case 49: 'X' + '49' + Math.random(); break;
case 50: 'Y' + '50' + Math.random(); break;
case 51: 'Z' + '51' + Math.random(); break;
case 52: 'a' + '52' + Math.random(); break;
case 53: 'b' + '53' + Math.random(); break;
case 54: 'c' + '54' + Math.random(); break;
case 55: 'd' + '55' + Math.random(); break;
case 56: 'e' + '56' + Math.random(); break;
case 57: 'f' + '57' + Math.random(); break;
case 58: 'g' + '58' + Math.random(); break;
case 59: 'h' + '59' + Math.random(); break;
case 60: 'i' + '60' + Math.random(); break;
case 61: 'j' + '61' + Math.random(); break;
case 62: 'k' + '62' + Math.random(); break;
case 63: 'l' + '63' + Math.random(); break;
  }
}

Tests:

Switch
usingSwitch(~~(Math.random()*64))
Object Literal
objLiteral[~~(Math.random()*64)]();
Array Literal
arrayLiteral[~~(Math.random()*64)]();
Map Literal
map.get(~~(Math.random()*64))();

Run results for: Switch vs Prepared Object Literal vs Prepared Array vs Prepared Map

Switch

Object Literal

Array Literal

Map Literal