Advice needed on __del__

[Brian Quinlan]

phil wrote:
> I'm probably dense and don't quite get the point, even though I
> have coded about 200,000 lines of Python and coded .5 million lines of
> C before there was a C++
> 
> A class instance based language doesn't have to BE C++ to have a
> destructor method.

Very true. But meaningful finalizers are a difficult problem in 
languages like Python. For example:

class A:
     def __del__(self): print self.b

class B:
     def __init__(self, a): self.a = a
     def __del__(self): print self.a

a = A()
a.b = B(a)
del a

What should happen? How would you implement that behavior? How would 
you implement that behavior on Java and .NET (neither of which 
gaurantee that finalizers/destructors will be called).

> All I wanted to know is: is the apparent treatment of __del__
> which SEEMS to work fine for me in 2.3.4 deprecated or mangled
> in some later release or future plans.

__del__ is not currently gauranteed to do anything. Currently it does 
something. Depending on that something is a bad idea. Could you explain 
your problem in more detail - maybe we'll have some suggestions.

Cheers,
Brian