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@JobLeonard
Created December 5, 2017 17:18
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join vs concat when dealing with very long lists of single-character strings (http://jsbench.github.io/#26d1f3705b3340ace36cbad7b24055fb) #jsbench #jsperf
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<title>join vs concat when dealing with very long lists of single-character strings</title>
<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
<script src="./suite.js"></script>
</head>
<body>
<h1>Open the console to view the results</h1>
<h2><code>cmd + alt + j</code> or <code>ctrl + alt + j</code></h2>
</body>
</html>
"use strict";
(function (factory) {
if (typeof Benchmark !== "undefined") {
factory(Benchmark);
} else {
factory(require("benchmark"));
}
})(function (Benchmark) {
var suite = new Benchmark.Suite;
suite.add("random char +=", function () {
// random char +=
let s = '';
for (let i = 0; i < 1024 * 1024; i++) {
s += String.fromCharCode(Math.random() * 0x100 | 0);
}
});
suite.add("random char join", function () {
// random char join
let t = [];
for (let i = 0; i < 1024 * 1024; i++) {
t.push(String.fromCharCode(Math.random() * 0x100 | 0));
}
let s = t.join('');
});
suite.add("'a' +=", function () {
// 'a' +=
let s = '';
for (let i = 0; i < 1024 * 1024; i++) {
s += 'a';
}
});
suite.add("'a' join", function () {
// 'a' join
let t = [];
for (let i = 0; i < 1024 * 1024; i++) {
t.push('a');
}
let s = t.join('');
});
suite.on("cycle", function (evt) {
console.log(" - " + evt.target);
});
suite.on("complete", function (evt) {
console.log(new Array(30).join("-"));
var results = evt.currentTarget.sort(function (a, b) {
return b.hz - a.hz;
});
results.forEach(function (item) {
console.log((idx + 1) + ". " + item);
});
});
console.log("join vs concat when dealing with very long lists of single-character strings");
console.log(new Array(30).join("-"));
suite.run();
});
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