Hi Aurel,
Well, yes , it takes different kind of people to make the world go round ...
---------------------------------- someone else who tried, but succeeded
Introduction
When I first stumbled into Lisp advocacy on various corners of the web I was already an experienced programmer. At that point I had grokked what seemed at the time a wide range of programming languages. I was proud to have the usual suspects (C++, Java, C#, etc.) on my service record and was under impression that I knew everything there is to know about programming languages. I couldn't have possibly been more wrong.
My initial attempt to learn Lisp came to a crashing halt as soon as I saw some sample code. I suppose the same thought ran through my mind that ran through thousands of other minds who were ever in my shoes: "Why on Earth would anyone want to use a language with such horrific syntax?!" I couldn't be bothered to learn a language if its creators couldn't be bothered to give it a pleasant syntax. After all, I was almost blinded by the infamous Lisp parentheses!
The moment I regained my sight I communicated my frustrations to some members of the Lisp sect. Almost immediately I was bombarded by a standard set of responses: Lisp's parentheses are only a superficial matter, Lisp has a huge benefit of code and data being expressed in the same manner (which, obviously, is a huge improvement over XML), Lisp has tremendously powerful metaprogramming facilities that allow programs to write code and modify themselves, Lisp allows for creation of mini-languages specific to the problem at hand, Lisp blurs the distinction between run time and compile time, Lisp, Lisp, Lisp... The list was very impressive. Needless to say none of it made sense. Nobody could illustrate the usefulness of these features with specific examples because these techniques are supposedly only useful in large software systems. After many hours of debating that conventional programming languages do the job just fine, I gave up. I wasn't about to invest months into learning a language with a terrible syntax in order to understand obscure features that had no useful examples. My time has not yet come.
For many months the Lisp advocates pressed on. I was baffled. Many extremely intelligent people I knew and had much respect for were praising Lisp with almost religious dedication. There had to be something there, something I couldn't afford not to get my hands on! Eventually my thirst for knowledge won me over. I took the plunge, bit the bullet, got my hands dirty, and began months of mind bending exercises. It was a journey on an endless lake of frustration. I turned my mind inside out, rinsed it, and put it back in place. I went through seven rings of hell and came back. And then I got it.
The enlightenment came instantaneously. One moment I understood nothing, and the next moment everything clicked into place. I've achieved nirvana. Dozens of times I heard Eric Raymond's statement quoted by different people: "Lisp is worth learning for the profound enlightenment experience you will have when you finally get it; that experience will make you a better programmer for the rest of your days, even if you never actually use Lisp itself a lot." I never understood this statement. I never believed it could be true. And finally, after all the pain, it made sense! There was more truth to it than I ever could have imagined. I've achieved an almost divine state of mind, an instantaneous enlightenment experience that turned my view of computer science on its head in less than a single second.
That very second I became a member of the Lisp cult. I felt something a ninjitsu master must feel: I had to spread my newfound knowledge to at least ten lost souls in the course of my lifetime. I took the usual path. I was rehashing the same arguments that were given to me for years (only now they actually made sense!), hoping to convert unsuspecting bystanders. It didn't work. My persistence sparked a few people's interest but their curiosity dwindled at the mere sight of sample Lisp code. Perhaps years of advocacy would forge a few new Lispers, but I wasn't satisfied. There had to be a better way.
I gave the matter careful thought. Is there something inherently hard about Lisp that prevents very intelligent, experienced programmers from understanding it? No, there isn't. After all, I got it, and if I can do it, anybody can. Then what is it that makes Lisp so hard to understand? The answer, as such things usually do, came unexpectedly. Of course! Teaching anybody anything involves building advanced concepts on top of concepts they already understand! If the process is made interesting and the matter is explained properly the new concepts become as intuitive as the original building blocks that aided their understanding. That was the problem! Metaprogramming, code and data in one representation, self-modifying programs, domain specific mini-languages, none of the explanations for these concepts referenced familiar territory. How could I expect anyone to understand them! No wonder people wanted specific examples. I could as well have been speaking in Martian!
I shared my ideas with fellow Lispers. "Well, of course these concepts aren't explained in terms of familiar territory", they said. "They are so different, they're unlike anything these people have learned before." This was a poor excuse. "I do not believe this to be true", I said. The response was unanimous: "Why don't you give it a try?" So I did. This article is a product of my efforts. It is my attempt to explain Lisp in familiar, intuitive concepts. I urge brave souls to read on. Grab your favorite drink. Take a deep breath. Prepare to be blown away. Oh, and may the Force be with you.
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best Rob
