Run results for: RegExp inside vs outside loop

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/114.0

Browser: Firefox 114

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Outside, literal	90.7 Ops/sec
Inside, literal	96.2 Ops/sec
Outside, object	114.6 Ops/sec
Inside, object	58.9 Ops/sec

Script Preparation code:

const SIZE = 100000;
var chars = new Array(SIZE);
for (let index = 0; index < SIZE; index++) {
  chars[index] = String.fromCodePoint(
    Math.floor( Math.random() * 0x80 )
  );
}
var newChars = new Array(SIZE);

Tests:

Outside, literal
const regexp = /[\x00-\x1f\x7f]/g; for (const char of chars) { newChars.push(char.replace(regexp, "")); } console.log(newChars);
Inside, literal
for (const char of chars) { newChars.push(char.replace(/[\x00-\x1f\x7f]/g, "")); } console.log(newChars);
Outside, object
const regexp = new RegExp("[\x00-\x1f\x7f]"); for (const char of chars) { newChars.push(char.replace(regexp, "")); } console.log(newChars);
Inside, object
for (const char of chars) { newChars.push(char.replace(new RegExp("[\x00-\x1f\x7f]"), "")); } console.log(newChars);

Run results for: RegExp inside vs outside loop

RegExp inside vs outside loop

Outside, literal

Inside, literal

Outside, object

Inside, object