FatGeekUK

For the last 5 years I have classed myself as a Ruby on Rails developer. More recently, I realise I might possibly not be able to say that. I have been using Django a lot. I love RoR, but Django has some nice features. One of them is its ORM query mechanism, but things are changing....

I have written code in many languages (Basic, dBase, C, Sculptor 4GL, Assembler(many flavours) Perl, VBA, Javascript, Ruby and finally, Python.

For much of my experience of Ruby, I viewed Python as a sibling language. I thought Ruby and Python where rough equals in capability and complexity.

It took me about 3 months of Python coding to realise that this is very far from the truth.

Ruby and Python are not compadres, they are not friends, they don't work at the same level.

Ruby is much simpler than Python, it has far less 'language' there. For a start, python is a compiled bytecode language (you do notice all those PYC files all over the place don't you?).

That and its explicit binding mechanism (all those import statements at the head of a python file just make my ruby sensibilities scream!) make for a much quicker language than Ruby.

When you add to that all this stuff about decorators, metaclasses etc, that takes some getting used to. The whole idea that methods associated with an instance are actually method instances that need calling (forgetting @property for the moment).

When I read about that, my mouth started watering, there must be some REALLY interesting uses for that! But then I let it stew for a while.

Really, all that does is force the coder to recognise that there are properties and then there are methods, and to require the user to know the difference.

With ruby, you don't need that. Well, really, with ruby, there are really ONLY ever methods, this forces encapsulation much more completely than Pythons default behaviour does.

Looking more deeply into decorators and metaclasses, I realise that they are trying to give the same sort of versatility to Python that Rubys blocks give to it.

Blocks affect EVERY aspect of Ruby, without blocks ruby is a rather dull, flat language. With them, it is a rich, expressive language that allows for some truely lovely DSL applications. Python tries to get the same functionality from metaclasses, decorators etc, but it just feels that much more forced. Having to use several different but interlocking constructs to ALMOST do what Rubys blocks do. This MIGHT be as a consequence of limitations enforced on the language by its bytecode underpinnings, I don't know enough yet to be able to say.

So, I suppose my final word on the issue is that Ruby is NOT a sibling of Python, its probably more of a teenager to Pythons twentysomething. There is a LOT more depth to Python than there is to Ruby, but thats not because the depth brings anything extra, it's more because Rubys simplicity is sufficient for the task. Python IS faster though, and probably always will be.

The later the binding, the slower the runtime performance.

Rails is nice. Rails is REAL nice, but, you would expect me to say that, I am a rails developer.

One thing that rails is not nice about is efficiency.
It’s elegant, its compact, but, the simplest things can have unforseen consequences unless you understand at a fundamental level, whats going on.

The persistence layer of Rails is a class called ActiveRecord (Specifically, most of it is tied up in ActiveRecord::Base)

When you want to do something with every row in a table, or with a subset of rows, you want to do something like this…

ModelClass.find(:all).each do |item|
  ... do stuff ...
end

Take it from me, that would be bad.

What it would do is instantiate every row in the table as an object and build an array of those objects in memory. Thats fine if you have 10, 100, 1000 rows in that table, but what happens when you have 100000 or a million? Well, we would be in for a long wait.

Oh, I hope not.

I loved Java.

Java it its YOUTH, when you could buy two books, the tutorial and the reference, and that was all you needed. Before Swing, before Beans, before it exploded into the publishers wet dream it is now.

If you want to use Java on the web, you need to go on 3 two week courses, buy a rainforest worth of books and have a brain the size of a planet to encompass it all. To me, Java has gotten old, and fat and slow.

Thats why I love Rails, it started with 2 books, the Ruby reference and Pickaxe. Ahh, young, svelt, petite.

Rails is coming up for her second birthday, and I see signs, signs that my new darling is piling on the pounds.