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@jridgewell
Created March 5, 2019 19:24
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Array.map vs for-loop push (https://jsbench.github.io/#a4b27da6a1c42a778b010c396b450035) #jsbench #jsperf
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<title>Array.map vs for-loop push</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;
Benchmark.prototype.setup = function () {
let values = [];
for (i = 0; i < 20; i++) {
values[i] = { val: Math.random() };
}
};
suite.add("const newVals = values.map(i => i.val);", function () {
const newVals = values.map(i => i.val);
});
suite.add("const newVals = [];", function () {
const newVals = [];
for (let i = 0; i < values.length; i++) {
newVals.push(values[i].val)
}
});
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("Array.map vs for-loop push");
console.log(new Array(30).join("-"));
suite.run();
});
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