[Tutor] Simple code (was: Dumb Subclassing question)

[Kent Johnson]

>On a final note, it should be realised that OOP does not
>automatically imply writing less code. In fact for short programs
>it very often means more code, but hopefully the result is both
>more maintainable and more robust and flexible.

I think good programming practice often does imply writing less code, for 
two reasons. One is the DRY principle - Don't Repeat Yourself. In other 
words don't copy/paste identical sections of code. Don't duplicate data. 
Look for the common bits and factor them out into shared functions or 
classes or configuration files.

Second is YAGNI - You Aren't Gonna Need It -- which is closely related to 
"Do the simplest thing that could possibly work." These two principles of 
Extreme Programming are generally useful. The idea is, don't write code 
that you don't need today. Don't complicate today's design to accommodate 
tomorrow's anticipated needs, because when tomorrow comes there will often 
be something else that is more important.

One of the great things about Python is that you can write short programs 
without cluttering them up with needless OO complexity. A really simple 
program might start out as straight-line code without even any functions. 
As it gets more complicated you break it up into functions to keep it 
readable or to reuse bits of code. When you have several functions that are 
sharing common state variables, or when you need to duplicate some state 
variables, you introduce a class or two and maybe break the program up into 
multiple modules.

I'm all in favor of maintainable and robust code. I generally try to omit 
the flexibility until I actually need it. Simple is good.

Kent