Run results for: Regex vs Forloop Performance

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.0.0 Safari/537.36

Browser: Chrome 102

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
RegEx	2541434.5 Ops/sec
For Loop	273720.7 Ops/sec

HTML Preparation code:

var string = "passw)odas4gsdfsdf";

AخA
 
var string = "passw)odas4gsdfsdf";

Script Preparation code:

var string = "aaaaabbbbbccccddd";

 
var string = "aaaaabbbbbccccddd";

Tests:

RegEx

var s = string.match(/([a-zA-Z])\1*/g)||[];
return s.map(function(itm){
  return [itm.charAt(0), itm.length];
});

 
var s = string.match(/([a-zA-Z])\1*/g)||[];return s.map(function(itm){  return [itm.charAt(0), itm.length];});

For Loop

var result = [[string[0], 1]]
for(let i = 1; i < string.length; i++) {
  const char = string[i]
  const lastChar = result.at(-1)
  
  if(char === lastChar[0]){
	lastChar[1] = lastChar[1] + 1
  } else {
	result.push([char, 1])
  }
}

 
var result = [[string[0], 1]]for(let i = 1; i < string.length; i++) {  const char = string[i]  const lastChar = result.at(-1)    if(char === lastChar[0]){    lastChar[1] = lastChar[1] + 1  } else {    result.push([char, 1])  }}