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I got into Objective C because of swarm agent based modelling running on Windows/cygwin.

At first I thought they were talking about Swarm, a "attempt to gather up many different kinds of models that go under the heading of "agent-based modeling" and create a common language and programming approach." that I've worked with before. I'm surprised they went with the name of an established toolkit in another aspect of programming. Still, looks like a cool tool, another layer of abstraction to make distributed computing easier might make it more attractive to those that don't use it much at the moment.

Agent Based Modeling tools such as Repast, SWARM, and NetLogo are changing how social research is being done.

Remember that gcc has Objective-C support only because NeXT was forced to abide by the GNU GPL.

The Cult of Objective-C was founded in a flurry of dynamism intended to bring application programming into the modern age by combining the object-orientedness of Smalltalk with the strange pointer language of C hacks. They can often be found speaking sentences such as "Your small text parsing tool would have been far more elegant if you had used the model-view-controller design pattern" and "there's no sense in reinventing the hydrogen-powered kitchen sink with nanorobotic food-synthesis technology when the kit provides it for you."

Also known for other ostensibly unintelligible lines of code that, read aloud, sound like "NSKitchenSink kitchenSink equals NSKitchenSink kitchenSink" they are fond of the fact that what would be a three-hundred-line error in C++ involving templates of templates of templates becomes a mere warning in Objective-C, or, even worse, a runtime error to be discovered in three weeks' time. They also abhor the excessive parentheses caused by Java's strong compile-time type checking, far preferring three-hundred-character lines involving method names longer than Clinton's average State of the Union address.

Their number having dwindled to a small band of NeXT aficionados and other offshoot cults, the Cult of Objective-C has infiltrated Apple and has been thus growing its ranks through the use of shiny hardware and software lures.

Unfortunately, GNUStep is still a bit immature despite being around for many years. The reason there aren't commercial apps isn't because OpenStep isn't great/easy-to-use. It's more likely because the free OpenStep-like environment isn't stable/mature. QT and GTK are stable and mature but you don't see a plethora of non-niche commercial apps for those either.

Photoshop, I believe, is still mostly Carbon, not Cocoa. And, Photoshop on Linux is not a big market. If it were, there would be a QT or GTK Photoshop.

OpenStep has been popular in niche areas like banking and scientific apps. Swarm is developed mainly in cross-platform Obj-C. GNU gcc is still relatively behind in Obj-C support but I think Apple is helping to change that.

"Open Source requires participation; coding and community."

Does it? I don't think I have ever joined in the R-Project's mailing lists, but I use their software regularly. I know a lot of Linux users who lack the time or the skill to be kernel hackers.

You /do/ realize that most of us choose a platform that /does what we want it to/ and /works for us/ and not for religious reasons? For my purposes, Linux isn't ready for the desktop. If I joined the team, I could help it get ready, and in a matter of years, it might be with my help (it also might be without my help).

OTOH, I could just continue using my Mac and actually meet my deadlines and get my work done.

My spare time, incidentally, does go into an Open Source projects, either: The Swarm Project or Equation Service. You want me to start working on Linux now as well?

The Swarm Development Group

SFI

Complex Systems

Maybe it is just the marketing hype (or maybe it was the price) but I put the book back on the self.

The word "chaordic" is used as defined by Dee Hock (the person behind VISA) at http://www.chaordic.org and in his book "Birth of the Chaordic Age", which is essentially processes at the boundary between CHAos and ORDer and the social implications for how to design effective and responsive organizations for a dynamic society. The focus will be specially on computer simulations to support part of the goal defined here http://www.chaordic.org/who_hist.html#FourCond of: "Development of visual and physical models of chaordic organizations so that people have something to examine, experiment with, and compare to existing organizations. The models must contain the ethical and spiritual dimensions generally lacking in current models. In addition, computer simulations will need to be created to allow people to quickly see how clarity of purpose and principles allow institutions to self-organize, evolve over decades, and link in new patterns for an enduring constructive society."

People are invited to join the mailing list if they want at this page http://mail.freesoftware.fsf.org/mailman/listinfo/ simulchaord-discuss if you want to contribute to project related discussions or submit snippets of code (with the understanding contributions will be archived and can be incorporated into the project under the GPL license). I have been posting some artificial life links there related to modelling social systems to get things started -- one of the first was a link to the Atlantic Monthly article discussed in this Slashdot thread. For now, I am using use the list to record my own musings on related simulation issues including design, architecture, and use cases. I will also be posting my experiences as I try to create such simulations. Feel free to lurk for a while or chime in.

Here is a page leading to the entire mailing list archives (aroudn twenty messages so far): http://mail.freesoftware.fsf.org/pipermail/simulch aord-discuss/

The main project page is here: http://savannah.gnu.org/projects/simulchaord/ Cooperative development of releases of code is hosted on Savannah using CVS although I haven't yet put up any content (files or homepage) besides what's archived in the mailing list.

At the moment I am looking at using Swarm http://www.swarm.org as the base -- although I may just use Python instead -- or even use both for different aspects.

Another book on the topic that came out probably almost 10 years ago is "Emergent Computation", edited by Stephanie Forrest. It's out of print now, but I believe it was also published as a special issue of the Physica D journal. It was a conference proceedings. (I used to work at the Center for Nonlinear Studies and Santa Fe Institute, and Forrest was also around at the time.)

By the way, people interested in this stuff may be interested in checking out the Swarm simulation system, a multi-agent simulation environment. Some of the demos that come with it are the ant/pheromone models and so on, which e.g. Resnick also explored in StarLogo.

There are actually quite a few uses for this type of technology (see my Master's thesis for references ). The AI community has been looking at swarm intelligence and multi-agent systems for years. NASA has sponsored research on using ant-like behavior in multiple robots to explore Mars (advantages in redundancy, system memory, command and control, etc...).

Also, check out The Swarm Development Group - you can download some software to play with alife sims, visualize really efficient search patterns, etc...

The problem for many people who might otherwise be interested in it is that it depends on Objective-C which is a minority language by any standard. The good thing about Objective-C is that it's built in to most of the more recent versions of the GCC, the bad thing (to the unfamiliar) is that it's the bastard child of C and smalltalk. Myself, I find it eminently readable and robust, so I'll go on using it even if it is "totally irrelevant".

For free software it all comes down to personal preference, that's why there won't be a One True Interface ®. Now or in the future, that's not to say that certain interface idioms won't become nearly universal, or that better education and more experience won't raise people's expectations. But as long as anyone can modify or alter any aspect of their system (a good thing) and as long as the only check on releasing code is the choice of uptake on the part of the users there will be only minimal interface consistency.

This isn't a bad thing, the people who want consistent UI standards are acting as if the Free Software Movement is a unitary entity that should be acting in concert towards a defined goal. Ha.
Gnustep Links for the interested Official Gnustep site
Unofficial Gnustep Site
WindowMaker
Swarm Project not part of Gnustep, but an interesting use of Objective-C.

Ok, I haven't been doing Obj-C for too long, so this may be innacurate or incomplete yada yada.

I've only done work using my own code within a free set of libraries called Swarm, so I don't really know if there are method naming conventions between sets of code and the like. I think many common operations would be named the same. Basic things like object creation/destruction are certainly named the same.

Objective-C is more-or-less straight C with smalltalk classes grafted on top. Things like int, float, and C-style arrays aren't classes of any kind. However, most Obj-C compiler libraries have classes for arrays and other types of object collections. If you have an object of type id (literally, just a pointer to some object), there are some standard methods to see whether it's a particular class, whether it responds to a particular method or protocol set. There's been mention in comp.lang.objective-c about a higher-order-messaging scheme that one of the people is putting together to help handle things like performing actions over entire arrays, and it's done entirely within the language (no compiler changes). I haven't looked into it too much, but it looks pretty neat.