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.startsWith() vs. RegExp for short strings and short prefixes
(version: 1)
Comparing performance of:
.startsWith() vs RegExp
Created:
one year ago
by:
Registered User
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Script Preparation code:
const regexp = new RegExp(/^\-\-/); const prefix = "--"; const str = "--some-var"; const numTests = 10000;
Tests:
.startsWith()
let i = 0; while (i < numTests) { str.startsWith(prefix); i++; }
RegExp
let i = 0; while (i < numTests) { regexp.test(str); i++; }
Rendered benchmark preparation results:
Suite status:
<idle, ready to run>
Run tests (2)
Previous results
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Test case name
Result
.startsWith()
RegExp
Fastest:
N/A
Slowest:
N/A
Latest run results:
Run details:
(Test run date:
6 months ago
)
User agent:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36 Edg/141.0.0.0
Browser/OS:
Chrome 141 on Windows
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Embed
Embed Benchmark Result
<iframe src="https://measurethat.net/Embed?id=620398" width="100%" height="500px"></iframe>
Test name
Executions per second
.startsWith()
26134.9 Ops/sec
RegExp
8634.0 Ops/sec
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