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Run results for:
Array.prototype.concat vs unshift for joining two arrays
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Embed Benchmark Result
<iframe src="https://measurethat.net/Embed?id=618715" width="100%" height="500px"></iframe>
Run details:
User agent:
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:143.0) Gecko/20100101 Firefox/143.0
Browser:
Firefox 143
Operating system:
Windows
Device Platform:
Desktop
Date tested:
11 months ago
Benchmark engine:
Benchmark.js
direct mutation with splice + spread
12.4M/s
immutable with concat
10.6M/s
View exact numbers
Test name
Executions per second
✓
direct mutation with splice + spread
12,395,495 Ops/sec
immutable with concat
10,557,820 Ops/sec
Tests:
immutable with concat
var a = [ "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello" ] var b = [ "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello" ] var other = a.concat(b)
direct mutation with splice + spread
var a = [ "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello" ] var b = [ "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello" ] a.unshift(b);