Re: [Boost-users] boost 1.34.1 string algorithm.

From: Pavol Droba (droba_at_[hidden])
Date: 2007-08-01 03:27:39

Hi,

chun ping wang wrote:
> I was wondering is it really necessary to use string algorithms to find in
> 

I think, that meaning of the term 'necessary' is quite varying. There is
nothing that forces you to use Boost.StringAlgo if you don't need it.

> variable str2 the last occurence that does not contain a number between
> 1 and 9 and create a substr base on that.
> regulary i would use std::string strNew =
> str2.substr(str2.find_last_not_of("123456789"));
> 
> So 2 questions.
> 
> 1.) Whats the benefit of the string algorithm version of boost in this case.

Probably none. If your solution suits you well, there is no reason to
use an additional library.

> 2.) How would I do this using string algorithm instead.
> 

Since there is no direct find_last_not_of equivalent in the library, the
solution will be probably more complicated than yours.

Here is one solution, that popped in my mind:

using namespace boost;
using namespace std;

iterator_range<string::reverse_iterator> res=
      find_token(
        make_range(str2.rbegin(), str2.rend()),
          !is_digit());

string str_res(res.end().base(), res.begin().base());

(this might not work, I have not tested it).

Best Regards,
Pavol.