append on lists
Steve Holden
steve at holdenweb.com
Thu Sep 18 13:19:49 EDT 2008
Armin wrote:
> Duncan Booth wrote:
>> "Chris Rebert" <clp at rebertia.com> wrote:
>>> On Tue, Sep 16, 2008 at 1:20 AM, Armin <a at nospam.org> wrote:
>>>> [1,2,3,4,7].append(c) -> Is this a valid expression?
>>> Literally, no, because you can't call methods on literals.
>>
>> Rubbish. There is no restriction about calling methods on literals.
>> That expression is perfectly valid but has no practical use that I can
>> see.
>
> The semantic of [1,2,3,4,7].append(c) and [1,2,3,4,7] + c
> (with c = [8,9]) is identical, but the first expression doesn't provide
> a value. Strange by design ...
>
Have a care, there. The semantics are different.
lst = [1, 2, 3, 4, 7]
lst.append([8, 9])
makes lst
[1, 2, 3, 4, 7, [8, 9]]
whereas
lst = [1, 2, 3, 4, 7]
lst = lst + [8, 9]
makes lst
[1, 2, 3, 4, 5, 7, 8, 9]
I suspect you meant [1, 2, 3, 4, 5, 7] + [c]
regards
Steve
--
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Holden Web LLC http://www.holdenweb.com/
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