Understanding other people's code

[asimjalis at gmail.com]

On Friday, July 12, 2013 7:22:59 AM UTC-7, Azureaus wrote:
> Hi all,
> I've been asked to take over a project from someone else and to extend the functionality of this. The project is written in Python which I haven't had any real experience with (although I do really like it) so I've spent the last week or two settling in, trying to get my head around Python and the way in which this code works.

Here are some techniques I use in these situations.

1. Do a superficial scan of the code looking at names of classes, functions, variables, and speculate where the modification that I have to make will go. Chances are you don't need to understand the entire system to make your change.

2. Build some hypotheses about how the system works and use print statements or some other debugging technique to run the program and see if you get the result you expect.

3. Insert your code into a separate class and function and see if you can inject a call to your new code from the existing code so that it now works with the new functionality.

If you have to understand the details of some code, one approach is to try to summarize blocks of code with a single comment to wrap your mind around it.

Asim