debugging makes a person a better programmer

[Mike C. Fletcher]

broebel wrote:

>I'm just wondering,
>
>people tell me that helping to debug someone elses program is a really good
>way to learn to understand the language it's programmed in.
>  
>
One of the reasons that "debugging as learning" is often useful is that 
many modern systems are large, complex collections of loosely coupled 
components.  Zope, for instance, is almost impossible to grok fully 
without spelunking through with a debugger to see what actually happens 
with the security machinery, the traversal machinery, etceteras.  The 
debugging gives you a guide to "where to start reading the code".  Keep 
in mind that in these situations, you're not actually looking for bugs, 
you're just using the debugging tool to figure out what's going on under 
the covers.

As to the actual suggestion of trying to fix bugs to learn.  It can be a 
good way, but it really does need a mentor to make it an efficient 
operation.  If you want to pursue it, look at the bug-tracker for the 
project in which you're interested (this is particularly easy with 
SourceForge-hosted projects), and choose something that seems small.  
Email the developers of the project to let them know you'll be playing 
with the bug, (let them know that you're a new-ish developer).

Depending on the maturity and size of the projects, you may even find 
"how to get started hacking on X" documentation hanging around.  
Otherwise you'll often need to talk with the developers to make any real 
headway.  The developers of the project may even have a suggestion for 
what bug would be an appropriate first step.  If you're lucky, the 
developers will have failure-case code available (i.e. unit-tests) so 
that you can know when you've succeeded :) .

>My question is: from wich point of can someone start to try to help a
>programmer by debugging or testing a program.
>
>If indeed you already need a profound knowledge of the language than how can
>you learn something about it? except for the fact that you see other
>possibilities of way to programm.
>  
>
One of the ways that people often suggest is to read (and then play 
with) small samples of really well-written code.  The Python Cookbook 
(both the dead-trees and the online versions) is designed for this kind 
of learning.  This code will tend to have fairly low defect rates, but 
it is, in essence, a collection of the "verse literature" (poetry) of 
the language (where projects such as Zope or Twisted is the "prose 
literature", i.e. long-form/novels).

Personally, I'd suggest studying short-form examples of the art first 
(i.e. poetry), they tend to be easier to keep entirely within the mind, 
and will tend toward more varied expressions of what can be done.  Once 
you've been exposed to the possibilities, try spelunking through the 
larger and more heavily structured projects (e.g. Twisted, Zope).

Have fun, and good luck,
Mike

_______________________________________
  Mike C. Fletcher
  Designer, VR Plumber, Coder
  http://members.rogers.com/mcfletch/