question about for cycle

fdu.xiaojf at gmail.com fdu.xiaojf at gmail.com
Sat Sep 29 16:34:21 CEST 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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