Cristian Cardellino

class Coder extends Human with Geek

Why Did I Choose Scala?

So, on this entry I’ll put a halt on the series of tutorials I’ve been writing. Instead I think it’s time to give a personal opinion in why did I choose Scala as my new main language.

Before keep going on this, I’ll just state that this is a complete personal opinion on Scala, is completely subjective. The reason why I chose it is mine and doesn’t have to be your reason to choose it, but maybe you’ll find some useful insights on what advantages I think the language has.

So, a couple of friends and co-workers asked me “Why Scala over Python? (or any other language for that matter)”, I guess I’ve never answered with a full justification on why did I do it. Actually, I don’t think I have a real or valid justification more than “because I liked it”, but I do want to state some stuff that end up with me switching from a Python programmer to a Scala programmer.

I got bored

I don’t think this counts as a real “advantage”, but it’s definitely one of the main reasons. Before Scala I was a Python programmer for 4 years, and I just got bored. Programming in Python wasn’t fun anymore, wasn’t challenging enough. Don’t take this the wrong way, it’s not that I’ve learnt everything I could in Python, that’s completely ridiculous, I’m as far as learning or using all that Python has to offer as I can get. But, somehow, I wasn’t interested in learning new things in Python.

Maybe was the fact that in the Zen of Python “There should be one– and preferably only one –obvious way to do it”, which is a great way but not fun enough for me. But probably was the mere fact that 4 years with the same language was far more than what I wanted.

Nonetheless, I don’t regret knowing Python, is still a wonderful language to learn, specially for a starter programmer. Simple and plain, easy to read even if you coded it years ago.

And of course, with these I’m not saying Scala is better than Python, nor is that my intention. Scala and Python are just different, they offer different things and provide different ways for programming.

Functional Programming

Scala is a multi-paradigm language. It can be used with an imperative language orientation (much like Java, C++ or Python), but it’s designed with the idea of functional programming in it’s core.

Functional programming is something very different from imperative programming, and probably is not as natural as the latter. Is a paradigm harder to learn and even harder to master (at least from my point of view). And in general term has always been associated with the academia (with LISP or Haskell as references). However, when you start to use this paradigm, is extremely good in dealing with many issues, specially nowadays. For example, functional programming languages can handle concurrency like no other languages as they are stateless. Other nice features include the always useful pattern matching and the extremely powerful high-order functions.

There is a good article called Functional Programming For The Rest Of Us. Take a look at it, it’s an interesting read.

I learned the functional programming paradigm in the university, in my first courses of algorithms and data structures. Back then I used Haskell and to be honest I hated it. It wasn’t clear for me, it made me have headaches. But, I guess that with time I became mature enough to know the advantages of this paradigm.

You can tell me, if I like functional programming, why not LISP or Haskell then? Real purely functional programming languages. And it’s as simple as saying, it’s still not natural for me to use a purely functional language, it would take me too much time to code some functionalities. That’s why I prefer Scala, because, if I don’t know how to do something in the functional way I still can do it in the imperative way. It’s not the cleanest solution, I know, but when experimenting, it’s a solution. Then I can try to arrange it so it’s either all functional or all imperative.

Besides, after years of imperative programming in Python, it’s smoother to jump to a language that allows me to do things the way I used to do them instead of a language that makes me learn new ways for everything. Once I’ve mastered Scala I can jump to something more pure in the functional paradigm (that is, if Scala cannot accomplish it, which I doubt).

Finally, Scala, as a functional language, has been given the tools necessary to go reactive, making concurrency and distribution easier and giving a nice and elegant way to asynchronous programming.

Static Types

If there is a thing that Python lacks of are static types. Of course, this is a matter of pure perspective, since for some people this is an advantage of Python. You don’t have to deal with variable types so it’s a weight you take off your back.

This, however, is not the case for me. At the beginning I thought dynamic typing was a great feature, you could make reuse of variables without having to deal with them being already used. But, as I experienced in some codes I did across my time as Python coder, I realized most of the time is good to have a registry on what are the variables you are using and the type they have on them. Specially when I dealt with experimentations in Natural Language.

Still, the great thing that Scala has over static typed languages (think Java for example), is the fact that it packs a type inferrer. This makes the coding much easier and far less verbose than a Java application. Like it’s presented in the Scala Website: Don’t work for the type system. Let the type system work for you.

After years of dynamic typing, I come back once again to the good old static typing, and I’m happy with it.

Compilation to JVM

Scala compiles over the JVM, that’s why it’s called a JVM language (just like Jython, Clojure, Groovy or JRuby).

This compilation to Java bytecode gives Scala a couple of nice features. The very first is speed, as it compiles to something nearer to object code (and thus near to machine code), a typical Scala application is only 2 or 3 times slower than a C application, whereas a Python application can be up to 50 times slower than a C application.

The second great feature resides in its seamless interoperation with Java. As it is stated in the Scala Website: “Scala classes are ultimately JVM classes. You can create Java objects, call their methods and inherit from Java classes transparently from Scala. Similarly, Java code can reference Scala classes and objects.

In general terms, this is a very big deal. Why? It’s simple, because Java has been an industrial standard for years now, and that translated in hundred if not thousands of useful libraries written for Java that are completely useful for building Scala applications.

A programming language is as powerful as the libraries it has to back it up (that’s precicely why Java and C++ are top choices in the market). The more libraries, the less code you have to rewrite (an important principle in programming is to never reinvent the wheel). Scala is growing in libraries everyday, but the collection probably is not as large as Python’s. However, Java libraries' collection is as large (and probably even larger) as Python’s collection, and the fact that this are useful for Scala programs as well give a Scala a great advantage over many other new languages.

If you are asking, ok but, why not use Java then? Simple, I’ve never been a Java enthusiast, and although I respect the contribution it has given to the programming environment, I still prefer the less verbose code of Scala, and then again, Java is not a functional programming language.

A Cool Kid

Finally, the last reason I choose Scala as new toy to play with. In the last years, Scala community has grown a lot, and it’s in part because is a new technology or, a more slang way to say it: “it’s what cool kids are doing”.

Ok, maybe “cool kid” is way too arrogant to state it. Still, what I mean is that a big generation of early adopters in programming languages has been turning into one of these two new technologies these last couple of years: JavaScript, commonly a client-side language to give web applications a little more “dynamic”, has been increasing in usability since the launch of NodeJS (another new tool I’m interested in), using the JavaScript V8 engine to build side-server JavaScript applications; And the other one is Scala, with the reactive programming manifesto and the easiness in coding asynchronous applications.

Personally, I’ve never been an early adopter, I’ve always preferred a good old fashion stable Debian OS over a fancy latest model Ubuntu. But, as I stated before, I got bored, and as a result of that, I wanted to learn something new, something different, and Scala has been so far a smooth ride.

That’s all I had to say about this. I hope you liked my insight on this beautiful language and my post leads you to learn it. If you really put yourself into it you’ll find out the potential of this language is excellent and you won’t be regretted in adopting Scala.

Thank you for reading.