“Generic” iterator in c++

Question

I have:

void add_all_msgs(std::deque::iterator &iter);

How can I make that function \"generic\", so it can take any kind

Answer 1

If you want the compiler to check whether the iterator actually refers to Message objects, you can use a technique like the following.

template <typename InputIterator, typename ValueType>
struct AddAllMessages { };

template <typename InputIterator>
struct AddAllMessages<InputIterator, Message> {
  static void execute(const InputIterator &it) {
    // ...
  }
};

template <typename InputIterator>
void add_all_msgs(const InputIterator &it) {
  AddAllMessages<InputIterator, 
                 typename std::iterator_traits<InputIterator>::value_type>::execute(it);
}