[erlang-questions] Regular expression library (was Not an Erlang fan)
Mon Oct 1 23:19:08 CEST 2007
Sorry for the tardy response. I've been enjoying Erlang too much ... :-)
The results for your new version on pathological cases look outstanding.
How does this versions performance compare to the existing regexp for
simpler matches (without back references)?
PS - See y'all in Freiburg on Thursday & Friday
> On 27/09/2007, G Bulmer wrote:
> I guess it's the 'pathological' cases that worry me; "MY software
> NEVER breaks on the easy cases" :-)
> Seriously though, having a regexp with stable behaviour wins over one
> that gets the last 200% of performance *most of the time*, but is
> I did some tests using Russ Cox example comparing the old regexp
> module (not a good comparison i know) and a new version I am
> working on. The results confirmed his findings.
> N 15 18 20 22
> 25 30 40
> regexp 40 360 1570 6900 59000
> re 0.2 0.25 0.32 0.38 0.5
> 0.73 1.4
> All times in millisecs. The old regexp uses a backtracking algorithm.
> Which tends to show that we will have no problems with pathological
> cases. :-) If people feel that it is too slow for the simpler
> regexps and would prefer to use a C library then it is definitely
> important to choose the *right* library.
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