Splitting strings by regular expression in C++

In many cases, strings are not the right data structure, but in some they are. I need to parse a command line into words, and as I’m writing C++, I went shopping for the equivalent of split as it is available in every other language. Not so in C++. The question, obviously, has been asked a hundred times on Stackoverflow, and there is a canonical blog post describing 10 different ways how to split a string. I like this solution from Stackoverflow best and adapted it so that I don’t get empty elements in my result vector:

#include <regex>

vector<string>
split(const string& s) {
  vector<string> elems;

  regex re("\\s+");

  sregex_token_iterator iter(s.begin(), s.end(), re, -1);
  sregex_token_iterator end;

  while (iter != end) {
    if (iter->length()) {
      elems.push_back(*iter);
    }
    ++iter;
  }

  return elems;
}