Function modify_function

tests/reflection.cpp:27–31

template<typename...ArgsT>
void modify_function(cs::var &func, ArgsT &&...args) {
    int level = remove_protect(func);
    func.swap(cs::var::make<cs::callable>(std::forward<ArgsT>(args)...), true);
    set_protect(func, level);
}

CNI_ROOT_NAMESPACE {
    CNI_V(privileged_do, [](cs::var &val, const cs::var &func) {