[Tutor] Whats so good about OOP ?

[Kent Johnson]

Mark Kels wrote:
> Hi list !
> I want to know whats so great in OOP...
> I have learned some of it, but I don't understand why everybody like
> it so much...

- One of the great challenges in programming is managing complexity. A program of any size is too 
complex to hold in your brain all at once. Techniques for breaking up a program into understandable 
pieces are essential. OOP gives you a way to break up a program into self-contained bundles of code 
and data that become building blocks for other pieces of the program. OOP lets you create 
abstractions that become components or tools for other abstractions.

- OOP enables many techniques for organizing code and reducing duplication. Many design patterns use 
cooperating objects. For example Composite, Decorator, Facade, Proxy, Chain of Responsibility, 
Command, Mediator, Observer, State, Strategy, Template Method... :-)
http://c2.com/cgi-bin/wiki?CategoryPattern

> Can anyone give me an example for a task that could be done only with
> OOP or will be much simpler to do with it ?

See this essay for some simple examples:
http://www.pycs.net/users/0000323/stories/15.html

Most modern GUI toolkits are heavily object-oriented including Tkinter and wxPython. Having a widget 
as a clear abstraction is very useful.

Much of the Python standard library is object-oriented. Since Python offers a choice between 
object-oriented and procedural style, if a library module is implemented with objects then 
presumably the author thought it would be simpler that way.

Of course Python is profoundly object-oriented in its core - strings, integers, lists and dicts are 
all objects providing simple abstractions of complex behaviour.

Kent