swig/Examples/test-suite/cpp11_function_objects.i

/* This testcase checks whether SWIG correctly parses function objects
   and the templates for the functions (signature).
   Function objects are objects which overload the operator() function.
   The std::function does not provide any seamless support in the target languages yet.
*/
%module(directors="1") cpp11_function_objects

%rename(__call__) Test::operator();

%feature("director") Test;

/* We had to rename this in the C++ API being wrapped due to a collision with
 * a value typedef in newer ocaml headers, so use %rename to avoid having to
 * update all the runme files which use it.
 */
%rename(value) Test::the_value;

%inline %{
class Test {
public:
  int the_value;
  
  virtual void operator()(int x, int y) {
    the_value=x+y;
  }
  Test() : the_value(0) {}
  virtual ~Test() {}
};

Test test;

#include <functional>
std::function<void ( int, int )> pF = test;

int testit1(Test &new_test, int a, int b) {
  pF = std::ref(new_test);
  pF(a, b);
  return new_test.the_value;
}

int testit2(int a, int b) {
  test(a, b);
  return test.the_value;
}

%}