tomchristie/gist:6173731

## gistfile1.html
<html>
<body><div><label><input type="checkbox" checked="checked"> Capture</label></div>
<div><input type="button" value="[1, 2]" /> <input type="button" value="Array(1, 2);" /> <input type="button" value="{foo: 'bar'}" /> <input type="button" value="({}).foo = 'bar';" /></div>
<div><textarea></textarea></div></body>
<script>
alert(1);
    var capture = function() {
    var ta = document.querySelector('textarea')
    ta.innerHTML = '';
	ta.appendChild(document.createTextNode("Captured: "+JSON.stringify(arguments)));
	return arguments;
}
var original = Array;

var toggle = document.body.querySelector('input[type="checkbox"]');
var toggleCapture = function() {
    var isOn = toggle.checked;
    window.Array = isOn ? capture : original;
    if (isOn) {
        Object.defineProperty(Object.prototype, 'foo', {set: capture});
    } else {
        delete Object.prototype.foo;
    }
};
toggle.addEventListener('click', toggleCapture);
toggleCapture();

[].forEach.call(document.body.querySelectorAll('input[type="button"]'), function(el) {
    el.addEventListener('click', function() {
        document.querySelector('textarea').innerHTML = 'Safe.';
        eval(this.value);
    });
});
</script>
</html>
	<html>
	<body><div><label><input type="checkbox" checked="checked"> Capture</label></div>
	<div><input type="button" value="[1, 2]" /> <input type="button" value="Array(1, 2);" /> <input type="button" value="{foo: 'bar'}" /> <input type="button" value="({}).foo = 'bar';" /></div>
	<div><textarea></textarea></div></body>
	<script>
	alert(1);
	var capture = function() {
	var ta = document.querySelector('textarea')
	ta.innerHTML = '';
	ta.appendChild(document.createTextNode("Captured: "+JSON.stringify(arguments)));
	return arguments;
	}
	var original = Array;

	var toggle = document.body.querySelector('input[type="checkbox"]');
	var toggleCapture = function() {
	var isOn = toggle.checked;
	window.Array = isOn ? capture : original;
	if (isOn) {
	Object.defineProperty(Object.prototype, 'foo', {set: capture});
	} else {
	delete Object.prototype.foo;
	}
	};
	toggle.addEventListener('click', toggleCapture);
	toggleCapture();

	[].forEach.call(document.body.querySelectorAll('input[type="button"]'), function(el) {
	el.addEventListener('click', function() {
	document.querySelector('textarea').innerHTML = 'Safe.';
	eval(this.value);
	});
	});
	</script>
	</html>