[Tutor] recursive problem

[Walter Prins]

Just a quick contribution for what it's worth: One of the subjects being
implicitly talked about here is "introspection" -- you may want to google
that and see else you can find. That said, a nice article covering some of
Python's introspection features is presented here on IBM's site:
http://www.ibm.com/developerworks/library/l-pyint.html

<http://www.ibm.com/developerworks/library/l-pyint.html>Actually any user
that's used to doing introspection in the Python shell already has that same
tool at their disposal for programmatic introspection, e.g. the dir()
method.  (This is covered in the above article.)

So, perhaps it's an idea to call dir() on a given object and see whether the
object provides the necessary methods to function, e.g. __iter__,
__delitem__, __setitem__ and friends?

Here's some code which constructs a class from scratch, which contains 2
member variables, which are made available via list indexing by implementing
__getitem__ and _setitem__ and shows how you can then use that object as if
it's a list, as least as far as the first 2 elements are concerned.  Also
does some interrogation with dir() at the end.

http://pastebin.com/rRZpbham

Hope that helps,

Walter
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