From: Michael Neumann <mneumann@...>
Date: 2004-08-03T18:15:12+09:00
Subject: Re: performance stats of String#scan, strscan and a homemade approach

Simon Strandgaard wrote:
> because I recently have messed around with a ruby syntax colorer, 
> I needed to know more about the performance of #scan or if there
> were faster alternatives.. String#scan seems to be the fastest.
> 
> maybe this come others in handy.
> 
> --
> Simon Strandgaard
> 
> 
> bash-2.05b$ ruby h.rb
>                           user     system      total        real
> String#scan           0.810000   0.020000   0.830000 (  0.937981)
> strscan               1.110000   0.040000   1.150000 (  1.255724)
> homemade slicer       2.420000   0.130000   2.550000 (  2.648530)
> true
> true
> bash-2.05b$ expand -t2 h.rb
> require 'strscan'
> def strscan(string, re)
>   tokens = []
>   ss = StringScanner.new(string)
>   until ss.eos?
>     m = ss.scan(re)

There's no advantage in your case when using strscan. Try to store the 
positions of the tokens and not the scanned string itself (the token) => 
StringScanner#skip. But that might not work for you.

Regards,

   Michael