Iterate over object properties

iterate.js

/**
 * Iterates over the properties of an object and calls a callback function when the
 * key belongs to the object itself and not to its prototype chain.
 * 
 * The iterate method will iterate over all properties but can be stopped by 
 * returning true from the callback method. 
 * 
 * @param {Object}   source   The object whose properties should be iterated over
 * @param {Function} callback The function to be called for each property defined
 *                            on the source object itself and not its prototype
 *                            chain. 
 *                            The callback will be called with two params. The 
 *                            first param is the current property name (key) and 
 *                            the second param is the value of the current property.
 */
function iterate(source, callback) {
	for(var key in source) {
		if (source.hasOwnProperty(key)) {
			if (callback(key, source[key])) {
				break;
			}
		}
	}
}