std::map::const_iterator template compilation error

Question

I have a template class that contains a std::map that stores pointers to T which refuses to compile:

template 
class Foo
{
public         


        

Answer 1

You need:

typename std::map::const_iterator begin() const { return items.begin(); }

Or simpler

typedef typename std::map::const_iterator const_iterator;
const_iterator begin() const { return items.begin(); }

This is because const_iterator is dependent name on T so you need to tell compiler that it is actually type.