Very nice handling by CoffeeScript

smart.js

(function() {
  var Foo, a;
  var __slice = Array.prototype.slice;
  Foo = (function() {
    function Foo() {}
    return Foo;
  })();
  a = [1, 2, 4];
  (function(func, args, ctor) {
    ctor.prototype = func.prototype;
    var child = new ctor, result = func.apply(child, args);
    return typeof result === "object" ? result : child;
  })(Foo, ['abc'].concat(__slice.call(a)), function() {});
}).call(this);