Re: Splitting strings

From:
red floyd <redfloyd@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Thu, 19 Nov 2009 08:22:28 -0800 (PST)
Message-ID:
<b39ff387-46b0-4188-83a0-c305501e1a36@g31g2000vbr.googlegroups.com>
On Nov 19, 3:59 am, Alan Woodland <a...@aberystwyth.ac.uk> wrote:

Hi,

I was looking for a clean, generic way to split strings around a
character using STL algorithms. The best I could manage was this
example, which isn't exactly great to say the least.

#include <cassert>
#include <vector>
#include <algorithm>
#include <string>
#include <sstream>
#include <iterator>
#include <iostream>

namespace {
  template <typename T>
  struct SplitHelper {
    std::basic_ostringstream<typename T::value_type> next;
    std::vector<T> result;
    typename T::value_type match;

    static bool test(SplitHelper& h, const typename T::value_type c) =

{

      if (c == h.match) {
        h.result.push_back(h.next.str());
        h.next.str(T());
      }

      return c == h.match;
    }
  };

}

std::vector<T> split(const T& str, const typename T::value_type c='/') =

{

  SplitHelper<T> h;
  h.match = c;
  h.result.reserve(std::count(str.begin(), str.end(), c));
  std::remove_copy_if(str.begin(), str.end(),
std::ostream_iterator<typename T::value_type>(h.next),
std::bind1st(std::ptr_fun(&h.test), h));
  h.result.push_back(h.next.str());
  return h.result;

}

#include <iostream>
int main() {
  const std::string path = "Hello/cruel/world";
  const std::vector<std::string>& result = split(path);
  std::cout << result.size() << std::endl;
  assert(3==result.size());
  std::cout << result[0] << std::endl;
  std::cout << result[1] << std::endl;
  std::cout << result[2] << std::endl;
  return 0;

}

Is this really the tidiest way to do this using STL algorithms?
Obviously it wouldn't be hard at all to do just using a for loop and two
pointers, but I was trying to do this 'the STL way'.


What's wrong with using an istringstream?

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