fun with c++11

Recently, I'm updating my knowledge of C++ to C++11. It has become a more convenient language now, saving some input. At least, you don't have to type tedious codes such as

for (TContainer::const_iterator it = coll.begin(), end = coll.end(); it != end; ++it)

again and again. Since C++11, we have range-based loop, something that Perl, JavaScript and BASH already have years ago.

Speaking of Perl, today I found out how easy it is to implement a Perl-like join. Below is an example.

#include <cstdio>
#include <string>
#include <sstream>

class join
{
public:
    join(char ch) : m_sDelimiter(1u, ch) {}
    join(const char * sz) : m_sDelimiter(sz) {}
    template <typename T>
    std::string operator()(T && arg) {
        std::stringstream ss;
        ss << arg;
        return ss.str();
    }
    template <typename T0, typename... argTs>
    std::string operator()(T0 && arg0, argTs&&... args) {
        std::stringstream ss;
        ss << arg0 << m_sDelimiter << (*this)(args...);
        return ss.str();
    }
private:
    std::string m_sDelimiter;
};

int main(int argc, char * argv[])
{
    std::string && s = join(", ")("apple", 135, "banana", 2.46, "cherry");
    ::printf("%s\n", s.c_str());
    return 0;
}

Yes, I knew there were boost::join already, but boost::join doesn't allow us to join elements of different data types, which sometimes is not as convenient as Perl's built-in function join.