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Iterating across a filtered list

Drew olsonas at gmail.com
Tue Mar 13 14:54:07 EDT 2007 
On Mar 13, 2:42 pm, Paul Rubin <http://phr...@NOSPAM.invalid> wrote:
> If I can decipher your Ruby example (I don't know Ruby), I think you
> want:
>
>    for name,contact in contacts.iteritems():
>       if re.search('search', name):
>           print contact
>
> If you just want to filter the dictionary inside an expression, you
> can use a generator expression:
>
>   d = ((name,contact) for (name,contact) in contacts.iteritems() \
>                         if re.search('search', name))
>
>   print '\n'.join(d)   # prints items from filtered dict, one per line
>
> Note that d is an iterator, which means it mutates when you step
> through it.

Paul -

You're exactly on the mark. I guess I was just wondering if your first
example (that is, breaking the if statement away from the iteration)
was preferred rather than initially filtering and then iterating.
However, you're examples make a lot of sense are are quite helpful.

Thanks,
Drew
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