core (fixes #452) Add TracedCallback::IsEmpty

CHANGES.html

@@ -59,6 +59,7 @@ us a note on ns-developers mailing list.</p>
 <li>With the new support for IPv6 Nix-Vector routing, we have all the new APIs corresponding to IPv4 Nix-Vector routing. Specific to the user, there is an Ipv6NixVectorHelper class which can be set in the InternetStackHelper, and works similar to Ipv4NixVectorHelper.</li>
 <li>In class <b>Ipv4InterfaceAddress</b>, a new function IsInSameSubnet () is added to check if both the IPv4 addresses are in the same subnet. Also, it is consistent with <b>Ipv6InterfaceAddress::IsInSameSubnet ()</b>.</li>
 <li>In class <b>ConfigStore</b>, a new Attribue <b>SaveDeprecated</b> allows to not save DEPRECATED Attributes. The default value is <b>false</b> (save DEPRECATED Attributes).</li>
+<li>In class <b>TracedCallback</b>, a new function <b>IsEmpty</b> allows to know if the TracedCallback will call any callback.</li>
 </ul>
 <h2>Changes to existing API:</h2>
 <ul>

RELEASE_NOTES

@@ -35,6 +35,7 @@ New user-visible features
 - (nix-vector-routing) Nix-Vector routing supports topologies with multiple WiFi networks using the same WiFi channel object.
 - (config-store) OBSOLETE Attributes are not anymore saved.
 - (config-store) New ConfigStore::SaveDeprecated Attribute (default false) to avoid to save DEPRECATED attributes.
+- (core) Add TracedCallback::IsEmpty to know if a TracedCallback has any callback associated.
 
 Bugs fixed
 ----------

src/core/model/traced-callback.h

@@ -89,6 +89,11 @@ public:
    * \param [in] args The arguments to the functor
    */
   void operator() (Ts... args) const;
+  /**
+   * \brief Checks if the Callbacks list is empty.
+   * \return true if the Callbacks list is empty.
+   */
+  bool IsEmpty () const;
 
   /**
    *  TracedCallback signature for POD.
@@ -188,6 +193,13 @@ TracedCallback<Ts...>::operator() (Ts... args) const
     }
 }
 
+template <typename... Ts>
+bool
+TracedCallback<Ts...>::IsEmpty () const
+{
+  return m_callbackList.empty ();
+}
+
 } // namespace ns3
 
 #endif /* TRACED_CALLBACK_H */