result_or_void.hpp

#pragma once
 
#include <tuple>
 
namespace VIPRA {
struct VOID {
  template <typename... arg_ts>
  inline void operator()(arg_ts... /*unused*/) const noexcept
  {
  }
};
}  // namespace VIPRA
 
namespace VIPRA::Util {
 
template <typename>
struct result_or_VOID;
 
template <typename type_t>
struct result_or_VOID {
  using type = std::conditional_t<std::is_void_v<type_t>, VOID, type_t>;
};
 
template <typename data_t>
using result_or_VOID_t = typename result_or_VOID<data_t>::type;
}  // namespace VIPRA::Util