Questions to the FAQ

Stefan Seefeld seefeld at sympatico.ca
Tue Jul 13 22:46:33 CEST 2004


Josef Wolf wrote:

> - FAQ entry 6.5: "What is delegation?"
> 
>   AFAICS, the example in this FAQ-entry should create a derived class from
>   the file class. Therefore, shouldn't the first line of this class
>   definition read "class UpperOut(file):"?

no, because that wouldn't be delegation but inheritance. Delegation is 
*not* about subclassing, but about delegating a task to another object.

> 
>   How come self.__outfile to be the base class?
> 
> - FAQ entry 6.6:
> 
>   This FAQ entry makes a difference between new-style classes and classic
>   classes. An example is given for the new style and a hint is given how a
>   classic class would look like. But I can't see any difference in them:
>   The new-style example starts with "class Derived(Base):" and the hint for
>   the classic class is "class Derived(Base): ..." So what's the difference?

the example is about how an overridden method can call the base-class 
method. For both cases the same child/parent relationship is assumed.
The difference is in the spelling of "call the base' class method", 
which, with new-style classes uses 'super'.

Regards,
		Stefan



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