Is a "real" C-Python possible?

[Duncan Booth]

Christian Heimes <lists at cheimes.de> wrote:

> Python 2.6 and 3.0 have a more Pythonic way for the problem:
> 
> class A(object):
>     @property
>     def foo(self):
>         return self._foo
> 
>     @foo.setter
>     def foo(self, value)
>         self._foo = value
> 
>     @foo.deletter
>     def foo(self)
>         del self._foo
> 
> class B(A):
>     # one can even overwrite the getter in a subclass
>     @foo.getter
>     def foo(self):
>         return self._foo * 2
> 

That would be great if it worked, but it doesn't.

Fixing your typos (missing colons, spelling of deleter, and in B the 
decorator needs to refer to A.foo.getter):

Python 3.0a2 (r30a2:59405M, Dec  7 2007, 15:23:28) [MSC v.1500 32 bit 
(Intel)] on win32
Type "copyright", "credits" or "license()" for more information.

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IDLE 3.0a1
>>> class A(object):
    @property
    def foo(self):
        return self._foo

    @foo.setter
    def foo(self, value):
        self._foo = value

    @foo.deleter
    def foo(self):
        del self._foo

        
>>> class B(A):
    # one can even overwrite the getter in a subclass
    @A.foo.getter
    def foo(self):
        return self._foo * 2

>>> a = A()
>>> a.foo = 5
>>> a.foo
10
>>> A.__dict__['foo']
<property object at 0x01261F80>
>>> B.__dict__['foo']
<property object at 0x01261F80>

Unfortunately as currently implemented, getter setter and deleter just 
update the existing property, so the getter defined in B changes how the 
property works in A as well. I think the intention may have been that they 
should create a new property each time, but this isn't what has been 
implemented.