Method UserStruct

unittests/user_data_adapters.hpp:47–53

struct UserStruct
{
  UserStruct( std::int32_t i,
              SomeStruct * pointer,
              SomeStruct & reference ) :
    i32( i ),
    p( pointer ),
    ref( reference )
  { }

  UserStruct & operator=( UserStruct const & ) = delete;