dvdrtrgn/clone.js

## clone.js
if (document.getElementById('hello')) {
    document.getElementById('hello').innerHTML = 'Hello World - this was inserted using JavaScript';
}

var original_array = [],
    dup_array;

for (var j = 0; j < 1500000; j++) {
    original_array[j] = 9;
}

function test1() {
    dup_array = null;
    var timeStart, timeEnd;

    timeStart = (new Date()).getTime();
    dup_array = original_array.slice();
    timeEnd = (new Date()).getTime();

    document.getElementById('test1result').innerHTML = (timeEnd - timeStart);
    setTimeout(test2, 1000);
}

function test2() {
    dup_array = null;
    var timeStart, timeEnd;

    timeStart = (new Date()).getTime();
    dup_array = [];
    for (var i = 0, l = original_array.length; i < l; ++i)
    dup_array[i] = original_array[i];
    timeEnd = (new Date()).getTime();

    document.getElementById('test2result').innerHTML = (timeEnd - timeStart);
    setTimeout(test3, 1000);
}

function test3() {
    dup_array = null;
    var timeStart, timeEnd, l;

    timeStart = (new Date()).getTime();
    l = original_array.length;
    dup_array = new Array(l);

    for (var i = 0; i < l; ++i)
    dup_array[i] = original_array[i];
    timeEnd = (new Date()).getTime();

    document.getElementById('test3result').innerHTML = (timeEnd - timeStart);
}

function run() {
    test1();
}

document.getElementsByTagName('input')[0].value = "ready";

## index.html
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Array clone bakeoff</title>
<!--[if IE]><script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script><![endif]-->
<style> article, aside, figure, footer, header, hgroup, menu, nav, section { display: block; } </style>
</head>
<body>
    <table>
        <tr>
            <td>test1 slice</td>
            <td><span id="test1result" ></span></td>
        </tr>
        <tr>
            <td>test2 loop</td>
            <td><span id="test2result" ></span></td>
        </tr>
        <tr>
            <td>test3 loop fixed size</td>
            <td><span id="test3result" ></span></td>
        </tr>
    </table>
    <input type="button" value="wait" onclick="run()">
    <script src="clone.js"></script>
</body>
</html>
	if (document.getElementById('hello')) {
	document.getElementById('hello').innerHTML = 'Hello World - this was inserted using JavaScript';
	}

	var original_array = [],
	dup_array;

	for (var j = 0; j < 1500000; j++) {
	original_array[j] = 9;
	}

	function test1() {
	dup_array = null;
	var timeStart, timeEnd;

	timeStart = (new Date()).getTime();
	dup_array = original_array.slice();
	timeEnd = (new Date()).getTime();

	document.getElementById('test1result').innerHTML = (timeEnd - timeStart);
	setTimeout(test2, 1000);
	}

	function test2() {
	dup_array = null;
	var timeStart, timeEnd;

	timeStart = (new Date()).getTime();
	dup_array = [];
	for (var i = 0, l = original_array.length; i < l; ++i)
	dup_array[i] = original_array[i];
	timeEnd = (new Date()).getTime();

	document.getElementById('test2result').innerHTML = (timeEnd - timeStart);
	setTimeout(test3, 1000);
	}

	function test3() {
	dup_array = null;
	var timeStart, timeEnd, l;

	timeStart = (new Date()).getTime();
	l = original_array.length;
	dup_array = new Array(l);

	for (var i = 0; i < l; ++i)
	dup_array[i] = original_array[i];
	timeEnd = (new Date()).getTime();

	document.getElementById('test3result').innerHTML = (timeEnd - timeStart);
	}

	function run() {
	test1();
	}

	document.getElementsByTagName('input')[0].value = "ready";
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset=utf-8 />
	<title>Array clone bakeoff</title>
	<!--[if IE]><script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script><![endif]-->
	<style> article, aside, figure, footer, header, hgroup, menu, nav, section { display: block; } </style>
	</head>
	<body>
	<table>
	<tr>
	<td>test1 slice</td>
	<td><span id="test1result" ></span></td>
	</tr>
	<tr>
	<td>test2 loop</td>
	<td><span id="test2result" ></span></td>
	</tr>
	<tr>
	<td>test3 loop fixed size</td>
	<td><span id="test3result" ></span></td>
	</tr>
	</table>
	<input type="button" value="wait" onclick="run()">
	<script src="clone.js"></script>
	</body>
	</html>