Re: [Boost-users] [string algorithms] finding last digit

9 Sep 2008

      AMDG

Peter Barker wrote:
...
Hello,
I have the following program:
#include <string>
#include 
#include 
int main()
{
  std::string str("12.5e");
boost::last_finder(str,boost::is_digit());  // <--- is this sort of right?
}
What I'm trying to do is find the last occurence of a digit in my
string (and learn a bit more about Boost.StringAlgorithms!). Am I
going down the correct route here, and if so would someone be so kind
to add to my program to show how I could obtain and output the index?
The call operator for last_finder accepts two paramters which has
thrown me as I thought the range was defined at construction.
last_finder searches for the substring specified in the constructor,
in the string passed to the function call operator.  You can use
the standard library fairly easily in this case:

#include <string>
#include <algorithm>
#include <iostream>

#include 

int main()
{
    std::string str("12.5e");
    std::cout << (std::find_if(str.rbegin(), str.rend(),
        boost::is_digit()).base() - str.begin() - 1) << std::endl;
}

In Christ,
Steven Watanabe