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__init__ method for containers

List and deque disagree on what __init__ does. Which one is
right?

Python 2.5.1 (r251:54863, Apr 18 2007, 08:51:08) [MSC v.1310 32 bit (Intel)] on
win32
Type "help", "copyright", "credits" or "license" for more information.
>>from collections import deque
x = deque([0, 1])
x.__init__([2, 3])
x
deque([0, 1, 2, 3])
>>y = list([0, 1])
y.__init__([2, 3])
y
[2, 3]

test_deque.py even contains a test verifying its __init__
behavior, so perhaps deque has a good reason to differ from the
behavior of list.

Moreover, both methods use the same doc string, i.e.:

__init__(...)
x.__init__(...) initializes x; see x.__class__.__doc__ for signature

When implementing a list-like container extension type, is there
any reason to choose anything other than list-like behavior,
i.e., if you call __init__, you'll initialize the container?
deque's behavior doesn't make sense to me.

--
Neil Cerutti
One of the causes of the American Revolution was the English put tacks in
their tea. --History Exam Blooper
Dec 12 '07 #1
2 1051
On Dec 12, 7:22 am, Neil Cerutti <horp...@yahoo.comwrote:
List and deque disagree on what __init__ does. Which one is
right?
File a bug report and assign to me.
Raymond
Dec 12 '07 #2
On 2007-12-12, Raymond Hettinger <py****@rcn.comwrote:
On Dec 12, 7:22 am, Neil Cerutti <horp...@yahoo.comwrote:
>List and deque disagree on what __init__ does. Which one is
right?

File a bug report and assign to me.
Will do. Registration in progress.

--
Neil Cerutti
Dec 12 '07 #3

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