Strange constructor behaviour (or not?)

[Rolf Wester]

Hi,

when defining:

class A:
	def __init__(self, l=[]):
		self.l = l
a = A()
a.l.append(1111)
b = A()
print a.l

I get the output

[1111]

instead of an empty list. I guess it's because the default value in the 
constructor is constructed once and whenever the constructor is called 
without l being specified.

My work around is:

class A:
	def __init__(self, l=None):
		if l == None:
			self.l = []
		else:
			self.l = l

Is there a way to take the first definition but force the constructor to 
create a new empty list every time it is called?

Thanks in advance

Rolf Wester