tag.hpp
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21 
22 #ifndef NDN_CXX_TAG_HPP
23 #define NDN_CXX_TAG_HPP
24 
25 namespace ndn {
26 
30 class Tag
31 {
32 public:
33  virtual
34  ~Tag();
35 
41 #ifdef DOXYGEN
42  static constexpr int
43  getTypeId() noexcept
44  {
45  return <type-identifier>;
46  }
47 #endif // DOXYGEN
48 };
49 
50 inline
51 Tag::~Tag() = default;
52 
57 template<typename T, int TypeId>
58 class SimpleTag : public Tag
59 {
60 public:
61  static constexpr int
62  getTypeId() noexcept
63  {
64  return TypeId;
65  }
66 
69  constexpr explicit
70  SimpleTag(const T& value) noexcept
71  : m_value(value)
72  {
73  }
74 
78  operator T() const
79  {
80  return m_value;
81  }
82 
85  constexpr const T&
86  get() const noexcept
87  {
88  return m_value;
89  }
90 
91 private:
92  T m_value;
93 };
94 
95 } // namespace ndn
96 
97 #endif // NDN_CXX_TAG_HPP
provides a tag type for simple types
Definition: tag.hpp:59
constexpr SimpleTag(const T &value) noexcept
explicitly convertible from T
Definition: tag.hpp:70
static constexpr int getTypeId() noexcept
Definition: tag.hpp:62
constexpr const T & get() const noexcept
Definition: tag.hpp:86
Base class for packet tags that can hold any arbitrary information.
Definition: tag.hpp:31
static constexpr int getTypeId() noexcept
Definition: tag.hpp:43
virtual ~Tag()
Definition: data.cpp:25