Error when pass std::map as template template argument

Question

I defined a function like this, in which there is a template template class

template cl         


        

Answer 1

You don't really need template template parameter in the first place. You could make it

template
struct ForEachOf {
  void operator()(const Map& map,
      std::function func) const {
            for(const auto& pair : map) {
                func(pair.first, pair.second);
            }
        }
    };

or even

template 
void operator() (const Map& map, F func) const { ... }