| | Perl5 regexen: exponential backtracking behavior when mixing \n and \s
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Anyone out there running Perl 5.6 or higher? Try running this little test proggy that compares the approximate CPU execution times of two regexen: ---...---begin---...--- #!/bin/perl use strict; $^W = 1; sub cputime { my ($user, $sys, $cuser, $csys) (...) (24 years ago, 17-Dec-00, to lugnet.off-topic.geek)
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| | Re: Perl5 regexen: exponential backtracking behavior when mixing \n and \s
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(...) [lindsey@wolrab ~]$ uname -a Linux wolrab 2.2.16-22smp #1 SMP Tue Aug 22 16:39:21 EDT 2000 i686 unknown [lindsey@wolrab ~]$ cat /etc/redhat-release Red Hat Linux release 7.0 (Guinness) s/(?:\n[ \t]*)+$// 0 0.00 1 0.00 2 0.00 3 0.00 4 0.00 5 (...) (24 years ago, 17-Dec-00, to lugnet.off-topic.geek)
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| | Re: Perl5 regexen: exponential backtracking behavior when mixing \n and \s
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(...) Awesome. Was that Perl 5.6? So it's smart enough to compile \n\s into a DFA instead of an NDFA? Wow. --Todd (24 years ago, 17-Dec-00, to lugnet.off-topic.geek)
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| | Re: Perl5 regexen: exponential backtracking behavior when mixing \n and \s
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(...) yah, that's what I got as well: greywolf$ perl -v This is perl, v5.6.0 built for i686-linux guess 5.6 kicks bootie :) (24 years ago, 17-Dec-00, to lugnet.off-topic.geek)
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| | Re: Perl5 regexen: exponential backtracking behavior when mixing \n and \s
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(...) Yup! lindsey@wolrab|/afs/...dsey|[65]> /usr/bin/perl -v This is perl, v5.6.0 built for i386-linux Chris (24 years ago, 18-Dec-00, to lugnet.off-topic.geek)
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