Appending a list's elements to another list using a list comprehension
Marc 'BlackJack' Rintsch
bj_666 at gmx.net
Wed Oct 17 16:36:15 EDT 2007
On Wed, 17 Oct 2007 20:27:14 +0000, Debajit Adhikary wrote:
> I have two lists:
>
> a = [1, 2, 3]
> b = [4, 5, 6]
>
> What I'd like to do is append all of the elements of b at the end of
> a, so that a looks like:
>
> a = [1, 2, 3, 4, 5, 6]
>
> I can do this using
>
> map(a.append, b)
This is a bad idea as it creates a useless list of `None`\s, one for each
element in `b`.
> How do I do this using a list comprehension?
Not at all. The obvious solution here is ``a.extend(b)``.
> (In general, is using a list comprehension preferable (or more
> "pythonic") as opposed to using map / filter etc.?)
Some say yes.
Ciao,
Marc 'BlackJack' Rintsch
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