text: #pragma once
  
  #ifndef NDEBUG
  
  #include <stdexcept>
  
  #define REQUIRE_HAS_VALUE(required)                        \
      if (!required)                                         \
      {                                                      \
          throw std::logic_error(#required " must not set"); \
      }
  #else
  
  #define REQUIRE_HAS_VALUE(required)
  
  #endif
  