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c++booststring-parsingiterator-range

Is there a function for number parsing which works on iterators?

Is there a way in C++ or Boost to parse a number (unsigned long long, if possible) which works directly on wstring iterators? It should be as fast as std::stoull.

Solution

  • Boost.Spirit has an iterator-based API. From what I've read it should be even faster than the standard string conversion functions.

    #include <iostream>
#include <string>
#include <boost/spirit/include/qi.hpp>

int main()
{
    namespace qi = boost::spirit::qi;

    std::wstring s(L"4398046511104");

    unsigned long long n = 0;
    qi::parse( begin(s), end(s), qi::ulong_long, n );

    std::cout << n << std::endl;
}

    Live demo on Coliru.