How about "pure virtual methods"?

Jeff Shannon jeff at
Wed Dec 22 19:36:54 CET 2004

Fredrik Lundh wrote:

>Noam Raphael wrote:
>>Oh, and another thing - maybe "abstract" is a better name than "notimplemented"? notimplemented 
>>might suggest a method which doesn't have to be implemented - and raises NotImplementedError when 
>>it is called. What do you think?
>what's the difference?  no, really?

The difference would be that a derived class *must* override an 
"abstract" method, but has the choice of leaving a "notimplemented" 
method unimplemented -- one is obligate, the other optional.

Personally, all of this seems like more bother than it's worth to me.  
I'm perfectly willing to "struggle" along without abstract base classes 
enforcing an interface, and merely make do with unenforced, informal 
protocols...  but then, I'm hardly an expert in such matters.  (Or any 
other sort of matters, either.)  ::shrug::

Jeff Shannon
Credit International

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