class variables

[Bruno Desthuilliers]

Colin J. Williams wrote:
> Andre Meyer wrote:
>> Hi all
>>
>> I am trying to understand the magic of Python's class variables and
>> tried the following code (see below).
>>
>> Just out of curiosity, I tried to define a property that provides
>> access to a seemingly instancae variable which is in fact a class
>> variable.

class Foo(object):
  _v = 5

  @apply
  def v():
    def fget(self):
      return Foo._v
      # other solution [1] :
      # return self.__class__._v
    def fset(self, val):
      Foo._v = val
      # other solution [1] :
      # self.__class__._v = val
    return property(**locals())


[1] Depends on how you want this to work when subclassing Foo...


Gives :

>>> f1 = Foo()
>>> f2 = Foo()
>>> f1.v
5
>>> f2.v
5
>>> f1.v = 42
>>> f1.v
42
>>> f2.v
42
>>> Foo._v
42
>>>

>> All seems to work fine (case 4), but when a custom object is
>> assigned, an instance variable is created instead of using theproerty
>> (case 5).
>>
>> What goes wrong here?

I'm afraid there are too much problems with indentation in the posted
code to give any serious answer.

(snip)


-- 
bruno desthuilliers
python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
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