[Python-Dev] Re: Python-Dev Digest, Vol 9, Issue 16
edloper at gradient.cis.upenn.edu
Sun Apr 4 20:33:57 EDT 2004
>>>How would this be interpreted?
>>> x = 42
>>> def x(self) [propget]:
>>> "Doc string for x"
>>> return self.__x
>>>That is, there is already an (otherwise invalid) 'x' in the calling scope
>>>when propget() is called. Do the property doodads just need to be
>>>bulletproofed or should an exception be raised?
>>It's broken. I expect this to raise an exception at some point.
>>Beyond that, who cares?
> If so, then this decorator is a bad idea.
> I would expect 42 to be the initial value of the property x.
That doesn't make sense. If you want to set a default value, you'd say:
__x = 42
A property's getter/setter/deleter can perform arbitrary actions, and in
the general case there's no sensible way to define an "initial value"
for a property. E.g., consider:
return random.choice(['apple', 'orange', 'grape'])
x = property(getX)
If this still doesn't make sense, go read the docs for properties:
> Then it makes sense to put "x = 42" after the three property definitions
> (before the end of the class definition). Would that work?
No, that would just overwrite x with the value 42 (throwing away the
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