[EMAIL PROTECTED] wrote:
> Pierre Barbier de Reuille wrote:
[...]
>
> I thank you for your response. The equivalent of your solution is
> posted hereunder:
> class cA(object):
> count=0
> def __init__(self):
> self.__class__.count +=1
> @classmethod
> def getcount(cls):
> return cls.count
> def __del__(self):
> self.__class__.count -=1
> class cB(cA):
> count=0
> def __init__(self):
> super(cB,self).__init__()
> for klass in self.__class__.__bases__:
> klass.count +=1
>
> a=cA() ; b=cA(); c= cA()
> d=cB() ; e=cB(); f= cB()
> a.a=1;b.a=1;c.a=1;d.a=1;e.a=1;f.a=1
> g=cA()
> g.a=1
> print '#cA=',cA.getcount() # 7
> print '#cB=',cB.getcount() # 3
> del g
> print '#cA=',cA.getcount() # 6
> print '#cB=',cB.getcount() # 3
>
> There is nothing impossible in Python ;-)
>
> Alain
>
Well, nothing is impossible, but it is now much much more complex ! As a
proof of that, your version does not work completely :P (try deleting d
for example).
I add a working version, but you will also notice that I have to
*explicitly* walk over all the classes of the hierarchy, testing for the
one who have a "count" attribute, hoping that this attribute is indeed
for counting the number of objects and not anything else ... so the
solution is quite fragile and very slow.
class cA(object):
count=0
def __init__(self):
self.__class__.count +=1
for klass in self.__class__.__bases__:
if hasattr( klass, "count" ):
klass.count += 1
@classmethod
def getcount(cls):
return cls.count
def __del__(self):
self.__class__.count -=1
for klass in self.__class__.__bases__:
if hasattr( klass, "count" ):
klass.count -= 1
class cB(cA):
count=0
a=cA() ; b=cA(); c= cA()
d=cB() ; e=cB(); f= cB()
a.a=1;b.a=1;c.a=1;d.a=1;e.a=1;f.a=1
g=cA()
g.a=1
print '#cA=',cA.getcount() # 7
print '#cB=',cB.getcount() # 3
del g
del d
print '#cA=',cA.getcount() # 5
print '#cB=',cB.getcount() # 2
Pierre
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