Run results for: regex vs slice

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 15_6 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/103.0.5060.63 Mobile/15E148 Safari/604.1

Browser: Chrome Mobile iOS 103

Operating system: iOS 15.6

Device Platform: Mobile

Date tested: 2 years ago

Test name	Executions per second
regex	6684805.0 Ops/sec
slice	19436950.0 Ops/sec
while loop	43399536.0 Ops/sec
binary search	41295288.0 Ops/sec

Script Preparation code:

const s = 'b'.repeat(22) + '0'.repeat(10);

Tests:

regex
const s = 'bbbbbbbbbbbbbbbbbbbbbb0000000000'; const re = new RegExp('0+$'); const res = s.replace('re', '');
slice
const s = 'bbbbbbbbbbbbbbbbbbbbbb0000000000'; const idx = s.indexOf(0); const res = s.slice(0, i);
while loop
const s = 'bbbbbbbbbbbbbbbbbbbbbb0000000000'; let idx = s.length - 1; while (idx > 0) { if (s[idx] === '0') { idx--; } else { break; } } const res = s.slice(0, i + 1);
binary search
const s = 'bbbbbbbbbbbbbbbbbbbbbb0000000000'; let l = 0; let r = s.length - 1; let mid; while (l < r) { mid = (l + r) >> 1; if (s[mid] === '0') { r = mid; } else { l = mid + 1; } } const res = s.slice(0, r);

Run results for: regex vs slice

regex

slice

while loop

binary search