Web 3d.0 Oooh! Teh shiney!

The developers at 280North have come up with a desktop application in a browser:

http://280slides.com/

More interesting is the framework they developed to implement the Keynote clone:

http://objective-j.org/ (including Cappuccino when released)

While some have taken the view that Objective-C is more powerful than Javacript, the fact that the former has been implemented in the latter shows both languages are Turing complete and the question of "power" is misleading. It is more to do with how software is constructed, and the encouragement that specific languages implicitly lend towards particular approaches.

C++ encourages overloading type hierarchies with communication, thereby creating brittle structures that change when messages change. Smalltalk encourages a focus on messaging with a separate and independent mechanism, so that inheritance is not of such importance. Javascript is based on prototyping objects and comes even closer to Lisp-like freedom.

The trouble with too much freedom is similar to the trouble with C++. Given many ways of doing something, another problem is invoked when people use that freedom do things in many different ways! The situation to be solved then becomes less about how to do something, and more about how to put the different somethings together in a uniform way that can be debugged and maintained.

Features like "cut/paste", "undo", "drag-drop" are uniform features that go across a wide range of interfaces and objects, so they are difficult to implement in languages that have many ways to do things. C++ and Javascript emphasise functions, so a framework like Objective-J is needed to emphasise the more uniform approach of method calls instead.

There is another interesting library:

http://projects.gandreas.com/jskit/

The combination of Objective-J and JSKit creates the compelling possibility of using Objective-C flavoured Javascript as an interpretive layer over Cocoa, with that fast Squirrelfish engine powering the works. One language layer that can control both the browser and the desktop! For a moment there, I considered that and was tempted away from Nu.

Both approaches have a number of similarities, but Objective-J is still based on C (via Javascript) and Smalltalk. This means it is lacking Nu's ability to define domain specific languages and convenient syntax, as well as the ability to extend into logic programming and other conceptual domains. In short, it does not have "code is data, data is code".

As these kinds of language merges become more common (with the current focus on DSLs), this question will arise more often. I feel that Nu has leapt to the sweet spot of DSLs... the original Lisp.