Overriding 'to boolean' operator in python?
<p>I'm using a class that is inherited from list as a data structure:</p>

<pre><code>class CItem( list ) :
  pass
oItem = CItem()
oItem.m_something = 10
oItem += [ 1, 2, 3 ]
</code></pre>

<p>All is perfect, but if I use my object of my class inside of an 'if', python evaluates it to False if underlying the list has no elements.  Since my class is not just list, I really want it to evaluate False only if it's None, and evaluate to True otherwise:</p>

<pre><code>a = None
if a :
  print "this is not called, as expected"
a = CItem()
if a :
  print "and this is not called too, since CItem is empty list. How to fix it?"
</code></pre>
