Iterating across a filtered list

[Arnaud Delobelle]

On Mar 13, 8:53 pm, Bruno Desthuilliers
<bdesth.quelquech... at free.quelquepart.fr> wrote:
> Paul Rubin a écrit :

[snip]

> >  Iterators like that are a new Python feature
>
> List comps are not that new (2.0 or 2.1 ?):
> print "\n".join([contact for name, contact in contacts.items() \
>                   if search.match(name)])

You can write this, but:
   * it is difficult to argue that it is more readable than Paul's (or
my)  'imperative' version;
   * it has no obvious performance benefit, in fact it creates a list
unnecessarily (I know you could use a generator with recent python).

> > and they have
> > some annoying characteristics, like the way they mutate when you touch
> > them.
>
> While sequences are iterables, all iterables are not sequences. Know
> what you use, and you'll be fine.

...And know when to use for statements :)

--
Arnaud