April 28, 2012

Study, choices and focus

Choices, choices, choices.

In the past few weeks I've been looking into a number of things I would like to study in the coming months. On the database side I had a look at NoSQL solutions. Notably CouchDB, CouchBase and MongoDB. I installed all of these on my Mac and experimented a couple of hours with each of them.

Programming languages.

I had a look at Scala and Erlang. Languages I never used before and that both present me with a few new concepts. I implemented one chore in Scala and multiple chores in Erlang. I published my Scala chore and the Erlang equivalent on this blog (Erlang chore here, Scala chore here).

On Rosetta Code I completed three simple tasks in Erlang. Count occurrences of a substring, HQ9+ and Ceasar cipher. These are, from a computer science point of view, simple chores. The idea behind implementing them was not they would present me with an intellectual challenge. The goal was to get familiar with the syntax. To get a feel for the beauty or ugliness and the possibilities and limitations of these languages.


Now it's about time to make up my mind what to study the coming months. I can't study all these things in parallel. Next to the intellectual challenge this would present, I've got a day-time job to attend. Besides that the missus and our children, while very patient, also deserve attention. Luckily my Mac is in the living room. That gives me, the missus and the kids a sense of togetherness while each doing our own thing. Here's a difference with my previous live where a subject would totally "suck me in". Completely unable to react or respond to events in my environment. Now I happily chat with the missus or the kids while figuring out map/reduce in CouchDB or hammering out some code in Erlang or Scala.

Choice of language.

Back to the choice of language to study. The fact I implemented more chores using Erlang already gives a hint. Perhaps I didn't do justice to Scala. Perhaps I should have implemented more chores to get more proficient in Scala. But the truth is that Erlangs syntax is really, really simple. Scala's syntax is  more elaborate but the advantages of this more complex syntax over Erlang remain unclear.

Martin Oderski was quite upset when someone stated Scala was about to become the next C++. In my view Martin and his team already set the first steps in making Scala the next C++. It's difficult to top the ugliness of C++'s syntax. And let's be fair, Scala currently doesn't come close, But for me, Scala comes close enough to keep away from it for the time being. That does not mean Scala isn't worth studying. It is. It's capabilities and the fact it produces code for the world's most popular runtime will make it a popular language. No doubts about that.

Erlang's syntax is very simple and elegant. Some minor points ignored (e.g. the ugly "if" construct, the use of which is by the way not mandatory), Erlang's syntax is the ultimate application of "Occam's razor" and stands in stark contrast with Scala's elaborate and sometimes incromprehensible language constructs.

So the coming months I'll be studying Erlang and especially OTP. I'm excited about Erlang as a language and OTP as a framework for designing massively parallel and fault tolerant systems. The elegance simply grabbed me and implementing simple chores like the Ceasar Cipher gave me a feel of true elegance. It convinced me that Erlang is a language that allows me to express my ideas in a very elegant manner. Not because of my programming-abilities or my proficiency in Erlang but because of the elegance of the language.

Perhaps I didn't do right to Scala by implementing only a single chore. But the beauty and elegance of Erlang simply grabbed my attention while Scala's syntax repelled me. While Erlang's language constructs feel natural, elegant and simple, Scala's constructs sometimes feel artificial.

My point of view is that Martin Oderski is desperately in need of Occam's razor and is well advised to take the remark that Scala will be the next C++ as a kind and very relevant advise.

Nagging aspects in language choice.

I see two nagging aspects in my choice for Erlang vs Scala. One is Scala's Akka framework which is relevant without any doubt and really looks like a thing of beauty. The other aspect is the Play framework which looks very promising.


The fact that a small team is able to implement capabilities that rival Erlang's OTP framework is an accomplishment in itself. The relevant metrics in comparing Akka and OTP would be simplicity of use, performance and lines of code spent using Akka or OTP.

The concurrency provided by Akka and Erlang is based on Communicating Sequential Processes. In Erlang this is implemented as a language feature, while Akka is a framework written in Scala.

Erlang/OTP has a proven track record with respect to reliability and uptime. Many Erlang/OTP based systems showed uptimes of 5*9 or even better. In this respect Erlang is in a class of its own. It remains to be seen wether Scala/Akka will be able to deliver the same with equal or comparable cost in hardware or development effort .

Play framework.

Another compelling aspect of Scala is the "Play" framework. The value of such a framework is beyond imagination. Frameworks like Play and Akka will propell Scala, that's for sure. Just like Ruby on Rails and ActiveRecord propelled Ruby.

Truth is that the guys that implemented Play borrowed about 99% of their ideas from David Heinemeier Hanssons work on Ruby on Rails without adding significant new ideas. Play to me looks and feels like Rails. Been there, done that. In fact still doing it. So no real benefit in studying Play. That's not to say Play isn't worth studying. It is. Play's performance gain over frameworks like Ruby on Rails is tremendous.

Choice of database.

To be fair I must admit I have no experience with NoSQL databases like CouchDB, CouchBase, MongoDb or BigTable. A colleague of mine successfully used CouchDB in one of his projects saving him a ton of work.

My choice of NoSQL database has no foundation and is completely random. I picked MongoDB combined with Ruby to study for the coming months. Simply because the combination of MongoDB and Ruby could become relevant in my day-time job.

No comments:

Post a Comment