Lorenzo Di Gregorio wrote: > I had also thought of using "None" (or whatever else) as a marker but > I was curious to find out whether there are better ways to supply an > object with standard values as a default argument. > In this sense, I was looking for problems ;-) > > Of course the observation that "def" is an instruction and no > declaration changes the situation: I would not have a new object being > constructed for every instantiation with no optional argument, because > __init__ gets executed on the instantiation but test=A() gets executed > on reading 'def'. > > At this point I think there is no other way than using a marker as > suggested above multiple times, if I want to supply a new object with > default values for non-passed arguments.
Using None as default for mutable default argument is the common idiom for the problem you're having. -- http://mail.python.org/mailman/listinfo/python-list
