main and dependent objects

[Ulrich Eckhardt]

Am 13.09.2012 14:51, schrieb andrea crotti:
> I am in a situation where I have a class Obj which contains many
> attributes, and also contains logically another object of class
> Dependent.
>
> This dependent_object, however, also needs to access many fields of the
> original class, so at the moment we did something like this:
[...]
> I could of course passing all the arguments needed to the constructor of
> Dependent, but it's a bit tedious..

Jean-Michel already asked a good question, i.e. whether those two 
classes should be separate at all. I'll ask a similar question: Can't 
the shared data be put into a third, separate class? That way passing 
all the needed arguments wouldn't be tedious any more. Also, it makes 
clear that both outer and inner class depend on common data, but that 
the inner class doesn't depend on the outer beyond that.

Now, just to get at least something Python-specific into this, you could 
override the __getitem__ of the inner class and transparently look up 
the item in the outer class if the inner class doesn't have it.

Uli