javascript closure

// bad
var add_the_handlers = function (nodes) {
    var i;
    for (i = 0; i < nodes.length; i += 1) {
        nodes[i].onclick = function () {
            alert(i);
        }
    }
};

add_the_handlers(document.body.childNodes);

// good
var add_the_handlers = function (nodes) {
    var i;
    for (i = 0; i < nodes.length; i += 1) {
        nodes[i].onclick = function (i) {
            return function () {
                alert(i);
            }
        }(i);
    }
};

add_the_handlers(document.body.childNodes);