On Jun 3, 6:11 pm, [EMAIL PROTECTED] wrote: > Hello all, > > I have come across this issue in Python and I cannot quite understand > what is going on. > > class Param(): > def __init__(self, data={}, condition=False): > if condition: > data['class']="Advanced" > print data > > In the previous example, I expect the variable data to be re- > initialized every time I construct an object type Param. However, when > I do the following: > > Param(condition=True) > Param(condition=False) > > The second call still prints {'class': 'Advanced'} > > Shouldn't data be initialized to {} since it is the default in > __init__? Why would the state of data be preserved between two > independent instantiations? > > Any help would be greatly appreciated. > > M.
This must be by far the most FAQ.. unfortunately it seems it will remain for 3.x as well: http://www.python.org/doc/faq/general/#why-are-default-values-shared-between-objects -- http://mail.python.org/mailman/listinfo/python-list