[Tutor] Shared Class Attribute

[Eric Brunson]

Ricardo Aráoz wrote:
> Hi,
>   

Hi Ricardo,

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> if I have this class :
>
> class myClass :
>     ClassCount = 0
>     def __init__(self) :
>         (here I want to increment ClassCount for the whole class)
> 	self.InstanceAttr = 1
>   

You always reference a class variable by the class name:

 >>> class myclass:
...     count = 0
...     def __init__( self ):
...         myclass.count += 1
...
 >>> c = myclass()
 >>> print c.count
1
 >>> d = myclass()
 >>> print d.count
2
 >>> print c.count
2
 >>> e = myclass()
 >>> print e.count, myclass.count
3 3

Hope that helps.

Sincerely,
e.

> How would I increment the shared class attribute (ClassCount) from
> INSIDE the class?
> I can do it from the outside by stating myClass.ClassCount = 22 and it
> will change for all instances. But haven't found a way to do it from inside.
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