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+// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
+
+/*
+ This is an example illustrating the use of the member_function_pointer object
+ from the dlib C++ Library.
+
+*/
+
+
+#include <iostream>
+#include <dlib/member_function_pointer.h>
+
+using namespace dlib;
+using namespace std;
+
+// ----------------------------------------------------------------------------------------
+
+class example_object
+{
+public:
+
+ void do_something (
+ )
+ {
+ cout << "hello world" << endl;
+ }
+
+ void print_this_number (
+ int num
+ )
+ {
+ cout << "number you gave me = " << num << endl;
+ }
+
+};
+
+// ----------------------------------------------------------------------------------------
+
+int main()
+{
+ // create a pointer that can point to member functions that take no arguments
+ member_function_pointer<> mfp1;
+
+ // create a pointer that can point to member functions that take a single int argument
+ member_function_pointer<int> mfp2;
+
+ example_object obj;
+
+ // now we set the mfp1 pointer to point to the member function do_something()
+ // on the obj object.
+ mfp1.set(obj, &example_object::do_something);
+
+
+ // now we set the mfp1 pointer to point to the member function print_this_number()
+ // on the obj object.
+ mfp2.set(obj, &example_object::print_this_number);
+
+
+ // Now we can call the function this pointer points to. This calls the function
+ // obj.do_something() via our member function pointer.
+ mfp1();
+
+ // Now we can call the function this pointer points to. This calls the function
+ // obj.print_this_number(5) via our member function pointer.
+ mfp2(5);
+
+
+ // The above example shows a very simple use of the member_function_pointer.
+ // A more interesting use of the member_function_pointer is in the implementation
+ // of callbacks or event handlers. For example, when you register an event
+ // handler for a dlib::button click it uses a member_function_pointer
+ // internally to save and later call your event handler.
+}
+
+// ----------------------------------------------------------------------------------------
+
+
+