jsPerf.app is an online JavaScript performance benchmark test runner & jsperf.com mirror. It is a complete rewrite in homage to the once excellent jsperf.com now with hopefully a more modern & maintainable codebase.
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https://jsperf.com/negative-modulo/2
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https://jsperf.app/negative-modulo/2
Using ~foo instead of foo > -1 or foo != -1 for functions that may return -1 certainly is neat, but is there a difference in terms of performance?
Inspired by http://www.timmywillison.com/pres/operators/#tilde-useful.
<script>
var str = 'Hello world!',
match = str.indexOf('o'),
noMatch = str.indexOf('a');
</script>Ready to run.
| Test | Ops/sec | |
|---|---|---|
| > -1 when there’s a match | | ready |
| != -1 when there’s a match | | ready |
| Bitwise NOT (~) when there’s a match | | ready |
| > -1, no match | | ready |
| != -1, no match | | ready |
| Bitwise NOT (~), no match | | ready |
You can edit these tests or add more tests to this page by appending /edit to the URL.