Hello everybody,
I've banged my ahead around for a while trying to figure out why
multiple instances of a class share the same instance variable. I've
stripped down my code to the following, which reproduces my problem.
class Test(object):
def __init__(self, v=[]):
self.values = v
def addValue(self, v):
self.values += [v]
return
a = Test()
a.addValue(1)
print a.values # Should print [1]
b = Test()
print b.values # Should print empty list
b.addValue(2)
print a.values # Should print [1]
The output I get is:
[1]
[1]
[1, 2]
The output I am expecting is:
[1]
[]
[1]
Another strange thing is that if I initialize with a different value,
the new instance will not share the 'values' attribute with the other
two:
c = Test([9])
print c.values # Prints [9] as it should
print a.values # Still prints [1, 2]
There is something I clearly don't understand here. Can anybody
explain? Thanks!
Python 2.4.4 (#1, Oct 23 2006, 13:58:18)
[GCC 4.1.1 20061011 (Red Hat 4.1.1-30)] on linux2
Alfred J. Fazio,
[EMAIL PROTECTED]
--
http://mail.python.org/mailman/listinfo/python-list
