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Date: Mon, 18 Feb 2013 14:18:49 +0000
From: John Reid <johnbaronreid@gmail.com>
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To: Oscar Benjamin <oscar.j.benjamin@gmail.com>
Subject: Re: Differences creating tuples and collections.namedtuples
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On 18/02/13 14:12, Oscar Benjamin wrote:
> On 18 February 2013 13:51, John Reid <johnbaronreid@gmail.com> wrote:
>> On 18/02/13 12:03, Oscar Benjamin wrote:
>>> On 18 February 2013 11:47, John Reid <johnbaronreid@gmail.com> wrote:
>>>> Hi,
>>>>
>>>> I was hoping namedtuples could be used as replacements for tuples in all instances.
>>> namedtuples are not really intended to serves as tuples anywhere. They
>>> are intended to provide lightweight, immutable, hashable objects with
>>> *named* (rather than numbered) values.
>> If they are not supposed to be tuples then calling them namedtuples and
>> inheriting from tuple seems a little odd.
> You can use namedtuple instances in places that expect tuples.
> Inheriting from tuples enables them to be all the things I said:
> lightweight, immutable and hashable. The type object itself has a
> different interface for the constructor, though.
>
>
Then I can't use them in every place I use tuples. For example IPython
relies upon the type's interface for the constructor as part of a
serialization mechanism.

I wonder why they have a different interface. It seems to restrict their
usability. No doubt there were other factors involved in the design of
the interface.

John.