Strings formating approach

tuple_to_strings.cpp

#include <iostream>
#include <cstddef>
#include <tuple>
#include <utility>
#include <sstream>
#include <vector>

template <typename Tuple, typename F, std::size_t ...Indices>
void for_each_impl(Tuple&& tuple, F&& f, std::index_sequence<Indices...>) {
    using swallow = int[];
    (void)swallow{
        (f(std::get<Indices>(std::forward<Tuple>(tuple))), int{})...
    };
}

template <typename Tuple, typename F>
void for_each(Tuple&& tuple, F&& f) {
    constexpr std::size_t N = std::tuple_size<std::remove_reference_t<Tuple>>::value;
    for_each_impl(std::forward<Tuple>(tuple), std::forward<F>(f),
                  std::make_index_sequence<N>{});
}

template<typename ... Args>
std::string formatArgs(const std::string& fmt_str, const std::tuple<Args...>& args)
{
    auto outStr = fmt_str;
    auto stringArgs = std::vector<std::string>();
    for_each(args, [&stringArgs](auto x) {
        std::ostringstream os;
        os << x;
        stringArgs.emplace_back(os.str());
    });
    
    auto it = outStr.find("%1");
    int count = 0;
    while (it != std::string::npos)
    {
        if (count < stringArgs.size())
        {
            outStr.replace(it, 2, "");
            outStr.insert(it, stringArgs[count]);
            ++count;
            it = outStr.find("%" + std::to_string(count + 1));
        }
        else
        {
            break;
        }
    }
    
    return outStr;
}

template<typename ... Args> void setText(const std::string& string, Args ... args)
{
    std::cout << formatArgs(string, std::make_tuple(std::forward<Args>(args)...)) << std::endl;
}

int main(int argc, const char * argv[]) {
    setText("Hello %1 %2 %3 Bye", 1, "Polly", 34.5f);
    return 0;
}