Dhananjay Nene recently switched over to Python and has discovered that he is much happier writing programs in Python. We covered his first article in the series, and the end of that post gives an idea of why we think you should listen to him, and also subscribe to his blog. In the next article in the Python vs. Java series, he takes a few design principles of object-oriented programming and shows how to implement those using sample code in Java and Python.
An excerpt to whet your appetite:
Well, static typed languages use polymorphism as a powerful mechanism of extensibility. In other words, in many cases the extensions are likely to be newer derived types. Thus design the rest of your code to work on the base type and introduce the newer derived types later as required without having to necessarily change existing code. However static languages primarily depend upon inheritance as the vehicle for delivering polymorphism. Dynamic languages on the other hand depend upon duck typing. Duck typing supports polymorphism without using inheritance. In this context you need the same set of relevant methods to be implemented in each of the extension classes. The role of the abstract base class or interface as the one which specifies the contract / api has been made redundant. You can still choose to define a base class / interface if you want to, but you no longer have to.
The full article is a must read if you are a student of programming languages in general, and object-oriented programming in particular. If you are neither of those things, and if you plan to be in the software field for a while, then you seriously need to ask yourself, “Why not!?“.
Dhananjay Nene recently switched over to Python and has discovered that he is much happier writing programs in Python. He has a detailed post over at this blog on the reasons:
I think the most dominant impression from the last few months is that python does make programming feel a lot more easier and often more enjoyable. The feeling is not very different between riding a bicycle without gears then riding one with gears. In the latter case one just feels one can cover a lot more distance much more easily though any physicist will tell you the actual effort is not particularly different. It just feels like one has a much bigger toolbox (ie a wider assortment of tools) to work with and therefore the task seems simpler. Why do I think that way ? I believe the following features of python do help (in no particular order) :
* Concise Coding style : The code typically is much more concise, with much lesser verbosity
* Dynamic typing : You really do not need to worry about declaring data types and making sure the inheritance hierarchies especially for all the interfaces and implementations well laid out. The various objects do not even need to be in the same inheritance hierarchy – so long as they can respond to the method, you can call it. This is a double edge sword, but that doesn’t take away the fact that programming under dynamic types environment does seem a lot easier.
* Easier runtime reflection : Java seems to have all the reflection capabilities but I think these are just way too painful to use as compared to python. In python the entire set of constructs (classes, sequences etc.) are available for easy reflection. In case you need to use metaprogramming constructs, python really rocks.
* More built in language capabilities : Items such a list comprehensions, ability to deal with functions as first class objects etc. give you a broader vocabulary to work with.
* Clean indentation requirement : It took me about 2-3 days to get over it but, it seems that python code is much easier to read since if you do not indent it correctly it will be rejected.
I am a Perl person myself, and think similar thoughts about Perl, and I don’t really care for the forced indentations of Python. But Perl is really for disciplined programmers who don’t get carried away and start doing all the weird things that the language allows. For the indisciplined folks, I guess the forced indentation of Python is probably a good way to keep them in check.
Anyway, read the whole article. You should also read the post he wrote at the time he chose Python for this next project. In fact, subscribe to his blog. He writes detailed and insightful articles that, as a techie, you would do well to read. If you are interested in programming languages, I would recommend reading “Contrasting java and dynamic languages”, and “Performance Comparison – C++ / Java / Python / Ruby/ Jython / JRuby / Groovy”. And if you are a blogger, check out his tips for software/programming blogging.
Dhananjay is a Pune-based software Engineer with 17 years in the field. Passionate about software engineering, programming, design and architecture. For more info, check out his PuneTech wiki profile.