Run results for: regex vs startWith

Run details:

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/119.0

Browser: Firefox 119

Operating system: Ubuntu

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
regex	6216.2 Ops/sec
startWith	7478.9 Ops/sec

Script Preparation code:

var foo = ['+++', '---', '===', '@@@', null, undefined, '', 'foo'];
var test = [];

for (var i = 0; i < 1000; i++) {
  test = [...test, ...foo];
}

​x
 
var foo = ['+++', '---', '===', '@@@', null, undefined, '', 'foo'];var test = [];​for (var i = 0; i < 1000; i++) {  test = [...test, ...foo];}

Tests:

regex

test.map((x) => /^\+\-\=\@/.test(x) ? "'" + x : x);

 
test.map((x) => /^\+\-\=\@/.test(x) ? "'" + x : x);

startWith

test.map((x) => {
  if (
    x?.startsWith('+') ||
    x?.startsWith('-') ||
    x?.startsWith('=') ||
    x?.startsWith('@')
  ) {
    return "'" + x;
  }
    
  return x;
});

 
test.map((x) => {  if (    x?.startsWith('+') ||    x?.startsWith('-') ||    x?.startsWith('=') ||    x?.startsWith('@')  ) {    return "'" + x;  }      return x;});