"Robert" <webtour...@gmail.com> wrote
class Foo( object ):
... myid = 'Foo'
... def __init__( self ):
... pass
...
f1 = Foo()
f2 = Foo()
f1.myid = 'Bar'
This creates a myid instance variable in f1 which hides the class
variable.
You should always modify class variables via the class not an instance
(you can read them either way but I prefer to use the class for both
read
and write)
Foo.myid = 'SPAM'
f1.myid <----------------------- Why is "f1" not affected
by the Class variable change ?
'Bar'
Because this is accessing the instance variable not the class one.
You can get at the class variable from the instance usind __class__
but usually you don'tneed to. You know the class in context or you
want the instance data not the class data.
f1.__class__.myid
'SPAM'
HTH,
--
Alan Gauld
Author of the Learn to Program web site
http://www.alan-g.me.uk/
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