Calling a parent constructor

How to automatically invoke a parent object's constructor in JavaScript. In answer to this SO question, http://stackoverflow.com/questions/6617780/how-to-call-parent-constructor/9421550#9421550

JavaScript

function test(id) {
    document.write(id + "<br />");
}

function testChild() {
    testChild.prototype.apply(this, arguments);
    document.write('also doing my own stuff');
}
testChild.prototype = test;
var instance = new testChild('hi', 'unused', 'optional', 'args');