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The Finch and the Raccoon

Submitted by administrator on Thu, 06/05/2008 - 12:34.

The blogs on xml.com are down so I have reposed this here.

Have you ever wondered if the laws of evolution apply to computer languages? When you walk down the isle at your favorite bookstore, does it seam like there are actually more computer languages than last year? What forces are driving each of these new languages to evolve?

In 1835 Charles Darwin visited the Galapagos Islands. There he collected what he thought were about a dozen distinct species of birds. Upon returning to England he discovered that each of these species had evolved from a single species of finches. On the various Galapagos Islands the requirements for food gathering was different, but consistent over hundreds of thousands of years. Enough time for a single species to adapt to meet consistent requirements.

Consider the Raccoon: omnivores that have proved to be one of the most adaptable mammals on Earth. The Raccoon’s range has rapidly expanded into urban areas due to their ability to quickly adapt to new requirements before other animals have had time for the wheels of evolution to turn.

So goes it with computer languages. Some procedural languages can be quickly adapted to fill in the needs for a new niche. When the web was young, procedural languages like Java and JavaScript quickly filled in the need for a variety of tasks. As the requirements for building web applications stabilized, declarative systems like CSS, XForms and XQuery started to push procedural languages back into niche-areas. As these declarative languages stabilize and become worldwide standards, graphical tools are being created to allow non-programmers to create, manipulate and extend these systems.

This is why many of us believe their will always be some need for procedural programming, but certainly not for building standard web applications that are controlled by style sheets and user interaction forms. Like the finch, declarative languages need a little longer to evolve. It sometimes takes years for a small vocabulary of functional specification patterns to emerge and be given labels. Additionally, it can takes years for the standards bodies to agree on the best way to deliver these new languages in a set of semantically precise data elements that have unambiguous interpretations. Finally, it may take another few years for IT managers to realized that they really do lower costs if they avoid vendor-specific implementations and adopt worldwide standards.

When CSS first came out you may have been a little reluctant to let web designers play with a rules engine. As XForms becomes ubiquitous you may be resisting change because you have invested so much time and energy learning how to debug JavaScript (without a debugger). You can not hold back the forces of evolution…and now we all need to adapt to the declarative world or risk our own extinction.

If you are interested in more on this topic see my Presentation from the 2007 Semantic Technology Conference The Semantics of Declarative Systems

Declarative Systems and the Cambrian Explosion

Submitted by administrator on Sat, 04/28/2007 - 16:01.

I have been reading Carl Zimmer's book Evolution, The Triumph of an Idea and I have been startled about the similarities between the the Cambrian Explosion and the growth of declarative languages.



Just to recap (if you have not read the Wikipedia article yet) here is a quick summary. For the first 3.5 billions years, life on earth was mostly single celled animals. Then about 550 million years ago, the number of new multicellular complex-body-plan animals exploded. There are two salient reasons. First, we needed oxygen to breath. Before there was oxygen in the atmosphere respiration was not easy. Oxygen was a foundation for complex body plans on land. Second, life needed a genetic "tool kit" to build complex animal shapes. We needed the HOX genes for building complex body plans. After that happened, complex life forms did explode.



I am seeing the same thing appear in declarative languages. Declarative languages need foundations also. We needed ways for people to quickly create new languages (e.g. GUI XML Schema editors like XMLSpy) and ways to build consensus around the semantics of these new languages (wiki's, social networks, folkonomies and voting).



And next we need the declarative systems tool kits. Right now we have started to develop tools to allow XML Schemas to be quickly transformed into GUI XForms editors and we have XML databases that eliminated the need for complex middle tiers. We can put many of these tools in the hands of non-programmers and allow them to create domain-specific vocabularies and rule-based systems with GUI editors.



And when those tools mature we will see an explosion of declarative languages similar to the explosion of life forms 550 million years ago.



So what is your prediction? 1 year, 3 years, 5 years or 10 years from now? I think a small group of people could build this toolkit without millions of dollars of venture capital. There may even be open-source tools that do this in a few years. But I think the key is to combine the best of metadata registries, XML Schemas, transforms, XForms, XQuery and XML databases into a holistic declarative system.



And from here the many NEW ideas will evolve.

Metaphors for Declarative Systems

Submitted by administrator on Fri, 04/06/2007 - 14:31.

I am working on my presentation for the 2007 semantic technology conference. My topic is the semantics of declarative languages.



I am attempting to present to business strategists that may not appreciate how powerful the new XForms and XQuery standards are and how entire rich user experience web 2.0 applications can be built using these tools as long as the tools have RESTful interfaces.



My first consideration is to find the right metaphors. I am working with the evolution metaphor and the puzzle metaphor right now and it seems to be working well.



I have also done some research on Domain Specific Languages and I see that they have also used the evolution metaphor but I find that they are focused on building small languages that are specific to a group or project and they don't really look at the external semantics of the problem.



Please write me if you are also trying to explain the business benefits of either declarative languages to a non-technical audience and if you have found metaphors that get the key points across.




Thanks! - Dan