concat.h

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/// @file
///
/// Convenience function that concatenates arbitrary arguments, by
/// feeding them to an ostringstream.
 
#ifndef MYSQL_UTILS_CONCAT_H
#define MYSQL_UTILS_CONCAT_H
 
#include <sstream>  // std::ostringstream
#include <string>   // std::string
 
/// @addtogroup GroupLibsMysqlUtils
/// @{
 
namespace mysql::utils {
 
namespace internal {
 
// Helper for 'concat' (base case)
inline void concat_to_stringstream([[maybe_unused]] std::ostringstream &out) {}
 
// Helper for 'concat' (recursive)
template <class T, class... Args>
void concat_to_stringstream(std::ostringstream &out, T first,
                            Args... remainder) {
  out << first;
  concat_to_stringstream(out, remainder...);
}
 
}  // namespace internal
 
/// Convert all the arguments to strings and concatenate the strings.
///
/// This feeds all arguments to a `std::ostringstream`, so supports all
/// types for which `operator<<(std::ostringstream&, ...)` is defined.
///
/// @param args Arguments to concatenate.
///
/// @return The resulting std::string.
template <class... Args>
std::string concat(Args... args) {
  std::ostringstream out;
  internal::concat_to_stringstream(out, args...);
  return out.str();
}
 
}  // namespace mysql::utils
 
/// @}
 
#endif  // MYSQL_UTILS_CONCAT_H