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subclassing list

Hi,

I want to subclass "list". The documentation states to prefer subclassing
list instead of UserList. How to you clear the contents of a list subclass
without creating a new object?

Thanks in advance
Uwe
Jul 18 '05 #1
2 1902
class newList(list):
def clear(self):
self[:] = []

is one way.
HTH

Regards,

Fuzzy
http://www.voidspace.org.uk/python/index.shtml

Jul 18 '05 #2

[Uwe]
How [do] you clear the contents of a list subclass
without creating a new object?


Use the paranoia emoticon: "del x[:]". For example:
class L(list): .... pass
.... x = L()
x.append("Spam" )
del x[:]
x [] type(x) <class '__main__.L'>


with-thanks-to-Gordon-McMillan-ly y'rs,

--
Richie Hindle
ri****@entrian. com

Jul 18 '05 #3

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