Hello! I am looking for advice about the use of the "notifier" function in program_options::options_description with class methods. My problem seems very basic to mee, yet I wasn't able to find the (any) related documentation. Here is a minimal example of what I cannot get to work: struct test { void function(int i) {std::cout << i << std::endl;} void does_not_compile() { po::options_description desc; desc.add_options() ("option", po::value<int>()->notifier(&test::function), "Option") ; } }; Compilation fails with: […] test.cpp:62:82: instantiated from here /usr/include/boost/function/function_template.hpp:225:11: error: no match for call to '(boost::_mfi::mf1<void, test, int>) (const int&)' /usr/include/boost/bind/mem_fn_template.hpp:163:7: note: candidates are: R boost::_mfi::mf1<R, T, A1>::operator()(T*, A1) const [with R = void, T = test, A1 = int] /usr/include/boost/bind/mem_fn_template.hpp:184:7: note: R boost::_mfi::mf1<R, T, A1>::operator()(T&, A1) const [with R = void, T = test, A1 = int] Sorry if this is trivial. Your help is all the more appreciated! Carlos