[Python-Dev] if-syntax for regular for-loops

[Leif Walsh]

On Fri, Oct 3, 2008 at 6:10 AM, Andreas Nilsson <adde at trialcode.com> wrote:
> With that out of the way, on to todays subject:
> I use list comprehensions and generator expressions a lot and lately I've
> found myself writing a lot of code like this:
>
> for i in items if i.some_field == some_value: i.do_something()
>
> Naturally it won't work but it seems like a pretty straight-forward
> extension to allow compressing simple loops to fit on one line. The
> alternative, in my eyes, suggests there's something more happening than a
> simple include-test which makes it harder to comprehend.
>
> for i in items:
>        if i.some_field == some_value: i.do_something()
>
> One possibility of course is to use a generator-expression but that makes it
> look like there are two for loops and it feels like a waste setting up a
> generator just for filtering.
>
> for i in (i for i in items if some_field == some_value):
>        i.do_something()
>
> Stupid idea? Am I missing some obviously better way of achieving the same
> result?

It's been discussed already.  Essentially, all that saves is a newline
or two, which, as I think has been generally accepted, tends to hurt
readability.

Here's the full discussion:
http://www.mail-archive.com/python-dev@python.org/msg29276.html

Other than that, welcome!

-- 
Cheers,
Leif