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@jridgewell
Created November 8, 2018 23:53
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Iterating over collections of elements (http://jsbench.github.io/#33a883c12f8c75cd5e62bdf12359b8e0) #jsbench #jsperf
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<title>Iterating over collections of elements</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 () {
var div = document.createElement('div');
for (let i = 0; i < 500; i++) {
div.appendChild(document.createElement('div'));
}
function noop(o) { return o; }
};
suite.add("Simple for loop undefined, static list", function () {
// Simple for loop undefined, static list
var elements = div.querySelectorAll('div');
for (var i = 0; elements[i] != undefined; i++) {
noop(elements[i]);
}
});
suite.add("Complex for loop undefined, static list", function () {
// Complex for loop undefined, static list
var elements = div.querySelectorAll('div');
for (var i = 0, element; (element = elements[i]) != undefined; i++) {
noop(element);
}
});
suite.add("Length, static list", function () {
// Length, static list
var elements = div.querySelectorAll('div');
for (var i = 0; i < elements.length; i++) {
noop(elements[i]);
}
});
suite.add("Cached Length, static list", function () {
// Cached Length, static list
var elements = div.querySelectorAll('div');
for (var i = 0, length = elements.length; i < length; i++) {
noop(elements[i]);
}
});
suite.add("Simple for loop undefined, live list", function () {
// Simple for loop undefined, live list
var elements = div.children;
for (var i = 0; elements[i] != undefined; i++) {
noop(elements[i]);
}
});
suite.add("Complex for loop undefined, live list", function () {
// Complex for loop undefined, live list
var elements = div.children;
for (var i = 0, element; (element = elements[i]) != undefined; i++) {
noop(element);
}
});
suite.add("Length, live list", function () {
// Length, live list
var elements = div.children;
for (var i = 0; i < elements.length; i++) {
noop(elements[i]);
}
});
suite.add("Cached Length, live list", function () {
// Cached Length, live list
var elements = div.children;
for (var i = 0, length = elements.length; i < length; i++) {
noop(elements[i]);
}
});
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("Iterating over collections of elements");
console.log(new Array(30).join("-"));
suite.run();
});
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