1 files changed, 19 insertions, 3 deletions
diff --git a/include/dbus-c++/util.h b/include/dbus-c++/util.h
index b46732f..8b3806d 100644
--- a/include/dbus-c++/util.h
+++ b/include/dbus-c++/util.h
@@ -28,6 +28,8 @@
 #include <sstream>
 #include <iostream>
 #include <iomanip>
+#include <cassert>
+
 #include "api.h"
 #include "debug.h"
 
@@ -232,15 +234,29 @@ public:
 
 	R operator()(P param) const
 	{
-		/*if (_cb.get())*/ return _cb->call(param);
+		if (!empty())
+    {      
+      return _cb->call(param);
+    }
+
+    // TODO: think about return type in this case
+    // this assert should help me to find the use case where it's needed...
+    //assert (false);
 	}
 
 	R call(P param) const
 	{
-		/*if (_cb.get())*/ return _cb->call(param);
+		if (!empty())
+    {
+      return _cb->call(param);
+    }
+
+    // TODO: think about return type in this case
+    // this assert should help me to find the use case where it's needed...
+    //assert (false);
 	}
 
-	bool empty()
+	bool empty() const
 	{
 		return _cb.get() == 0;
 	}