The current one is single-inheritance, because it uses the prototype chain. It's a compromise between speed and usefulness. I'd prefer having multimethods (and maybe also multiple inheritance), but speed is a bit more important, as JavaScript is already quite slow.

So far I'm quite pleased with the single-inheritance and single dispatch solution, which basically works like that: https://gist.github.com/866506

As I needed a name, I just chose "Ralph" as that was the original code-name of Dylan (see http://en.wikipedia.org/wiki/History_of_the_Dylan_programmin...). I'm currently implementing a web-based IDE for the OpenDylan compiler (http://www.opendylan.org/), called "Hula" (original code-name of Apple's IDE, see http://wiki.opendylan.org/wiki/view.dsp?title=AppleDylanScre...). The work-in-progress is at https://github.com/turbolent/hula.

If you're interested in a demo, let me know.

Other than being obviously new, this is pretty cool.

Edit: Would there be a better way to fix it than to add functions like this?

  function adder() {
    var args = Array.prototype.slice.call(arguments);
    return args.reduce(function(a, b){return a + b})
  }

  function subtractor() {
    var args = Array.prototype.slice.call(arguments);
    return args.reduce(function(a, b){return a - b})
  }

  function multiplier() {
    var args = Array.prototype.slice.call(arguments);
    return args.reduce(function(a, b){return a * b})
  }

  function divider() {
    var args = Array.prototype.slice.call(arguments);
    return args.reduce(function(a, b){return a / b})
  }

Fair point.

BTW what's interesting about yield based versus lazy evaluation (functional stream) based sequence generation? Advantages of the latter are that they can easily be understood as sequences and thus further processed by lazy versions of the known sequence processing functions (map etc.), also they can be re-read multiple times, which you just made impossible for yield by not basing it on call/cc :).

Although, I don't know that those things make it more practical than Scheme. Just more desirable to a subset of people who like that sort of thing.