Re: [boost] Doubt about regex speed.

From: John Maddock (john_at_[hidden])
Date: 2005-11-22 12:56:11

> I would like know if I use regex to do this I will have improvement in
> performance of my system, or I will have delay in my system?
>
> My regex to validate this message is:
> "\\d{1,5};1;\\d{1,8};\\d{16};\\d{3};\\d{4};\\d{1,8};([0-9]|10|11|12);[012]"
>
> My code sample (in old version I need same about 300 lines to do the
> same):

Well it probably depends on the quality of your existing code :-)

You shouldn't see any noticable slow down, especially if you re-use 
match_results structures: almost all the overhead is in allocating memory 
for the array of results, so as long as you re-use the match_results 
structure it should be pretty quick.  I had a quick look at your regular 
expression and that looks as good as it's going to get as well.

The short answer though is to try it out :-)

Regards, John.