From: Christian Neukirchen <chneukirchen@...>
Date: 2005-11-23T01:32:46+09:00
Subject: Re: Optimization anyone

ts <decoux@moulon.inra.fr> writes:

>>>>>> "H" == Horacio Sanson <hsanson@moegi.waseda.jp> writes:
>
> H> Regexp.new("#{key1}\.*#{key2}|#{key2}\.*#{key1}")
>
>  vs
>
> H>    r1 =  Regexp.new("#{key1}\.*#{key2}")
> H>    r2 =  Regexp.new("#{key2}\.*#{key1}")
>    
> H> Is this expected when using regular expressions?? 
>
>  yes, ruby has some optimizations. For example with the regexp /abc.*def/

Do you know how oniguruma does that, per chance?

> svg% ruby -rjj -e '/abc.*def/.dump'
> Regexp /abc.*def/
>   0	exactn "abc" (3)
>   1	anychar_repeat
>   2	exactn "def" (3)
>   3	end
> must : abc
> optimize : exactn
> svg% 
-- 
Christian Neukirchen  <chneukirchen@gmail.com>  http://chneukirchen.org