Object.deepFreeze

gistfile1.js

/**
 * Object.deepFreeze
 * Licensed under the MIT
 * @author: Alexander Guinness
 * @version: 1.1
 * @date: Fri Jun 27 17:26:00 2011
 **/

if (!Object.deepFreeze && Object.freeze && Object.isFrozen) {
	Object.deepFreeze = function(object)
	{
		var is = Object.prototype.toString, value;

		if (!object)
			throw new TypeError('Object.deepFreeze: ' + object + ' is not callable!');

		for (key in object)
		{
			value = object[key];

			if (is.call(value) === '[object Object]' && Object.prototype.hasOwnProperty.call(object, key) && !Object.isFrozen(value))
				Object.deepFreeze(value);
		}

		return Object.freeze(object);
	}
}