Run results for: single regex vs double regex vs for loop

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/101.0.4951.64 Safari/537.36

Browser: Chrome 101

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
regex combined	1041472.2 Ops/sec
double regex	1437669.6 Ops/sec
for loop	119529.0 Ops/sec

Script Preparation code:

var str = 'aasd-asdasd-fegdfg-werwerwer-dsfsdfsdf-sadfsdfsdf-asd-asdasdasdasd-asdasdasd-dssdfhsd-dsfsdfsd-sdfsdfsdf';
var size = str.length;
var regexCombined = /(^.)|-/g;
var regexFirst = /^./
var regexDash = /-/g

Tests:

regex combined
return str.replace(regexCombined, (s) => s === '-' ? ' ' : s.toUpperCase())
double regex
return str.replace(regexDash, ' ').replace(regexFirst, s => s.toUpperCase())
for loop
var result = ''; var i = 0; var char = ''; for (i = 0; i < size; i++) { char = str[i]; if (i === 0) { result += char.toUpperCase(); } else { result += char === '-' ? ' ' : char ; } } return result

Run results for: single regex vs double regex vs for loop

regex combined

double regex

for loop