custom-char

#define FMT_HEADER_ONLY
#include "format.h"

struct Syschar {
  char c;
  Syschar(char c = 0) : c(c) {}
  operator char() const { return c; }
};

namespace fmt {
namespace internal {
template <>
class CharTraits<Syschar> : public BasicCharTraits<Syschar> {
 public:
  static Syschar convert(char value) { return value); }
  static Syschar convert(Syschar value) { return value; }

  template <typename T>
  static int format_float(Syschar *buffer, std::size_t size,
      const Syschar *format, unsigned width, int precision, T value) {
    // floating point formatting goes here
    return 0;
  }
};
}
}

namespace {
template <>
inline Arg::StringValue<Syschar> ignore_incompatible_str(
    Arg::StringValue<wchar_t>) { return fmt::internal::Arg::StringValue<Syschar>(); }
}

void print(const Syschar *format_str, fmt::ArgList args) {
  fmt::BasicMemoryWriter<Syschar> w;
  fmt::BasicFormatter<Syschar> f(w);
  f.format(format_str, args);
  const Syschar *c = w.c_str();
  while (*c)
    std::putc((c++)->c, stdout);
}
FMT_VARIADIC(void, print, const Syschar *)

int main() {
  const Syschar str[] = {'t', 'e', 's', 't', '\0'};
  print(str);
}