question about for cycle
fdu.xiaojf at gmail.com
fdu.xiaojf at gmail.com
Sat Sep 29 10:34:21 EDT 2007
tokland at gmail.com wrote:
> On 29 sep, 12:04, "fdu.xia... at gmail.com" <fdu.xia... at gmail.com> wrote:
>
>> for i in generator_a: # the first "for" cycle
>> for j in generator_b:
>> if something_happen:
>> # do something here ..., I want the outer cycle to break
>> break
>
> Do you like this?
>
> generator_ab = ((x, y) for x in generator_a for y in generator_b)
> for i, j in generator_ab:
> if condition:
> # do something
> break
>
In this case, the tuple generator_ab must be generated first. Sometime
it maybe a waste to generate all possible combinations of i,j first.
I have googled and found the PEP-3136(Labeled break and continue),
which has been rejected. I have also read why Guido rejected this PEP(
http://mail.python.org/pipermail/python-3000/2007-July/008663.html),
but I still think labeled break and continue is a good feature in my
case.
Regards,
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