Message 151221 - Python tracker

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In-reply-to
Author	terry.reedy
Recipients	alex, ericp, ezio.melotti, pitrou, terry.reedy
Date	2012年01月14日.04:10:04
SpamBayes Score	2.0031763e-05
Marked as misclassified	No
Message-id	<1326514205.75.0.0718099729581.issue13723@psf.upfronthosting.co.za>

Content
I believe it is a known fact that repeated repeats, like (...+)*, make for slow matching (if they work at all) with the current re engine. [I would not be surprised if Perl does some special casing to (in effect at least) rewrite the re to your second version.] This is not going to be improved in 2.7, nor immediately in 3.x. You can try the regex module on pypi, but it may act the same. I suspect there are similar issues like this on the tracker. Best to write the re properly. [Antoine or Ezio: If you think I am mistaken in closing this, please reopen.]

Content

I believe it is a known fact that repeated repeats, like (...+)*, make for slow matching (if they work at all) with the current re engine.
[I would not be surprised if Perl does some special casing to (in effect at least) rewrite the re to your second version.] This is not going to be improved in 2.7, nor immediately in 3.x. You can try the regex module on pypi, but it may act the same. I suspect there are similar issues like this on the tracker. Best to write the re properly.
[Antoine or Ezio: If you think I am mistaken in closing this, please reopen.]

History
Date	User	Action	Args
2012年01月14日 04:10:05	terry.reedy	set	recipients: + terry.reedy, pitrou, ezio.melotti, alex, ericp
2012年01月14日 04:10:05	terry.reedy	set	messageid: <1326514205.75.0.0718099729581.issue13723@psf.upfronthosting.co.za>
2012年01月14日 04:10:05	terry.reedy	link	issue13723 messages
2012年01月14日 04:10:04	terry.reedy	create

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