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template class with nested iterator

obice (5)
Hi everyone, I've been fighting for hours on a problem and can't figure out the solution. Maybe some of you ran into something like this already and can help me understand the compiler's complaint? Thanks in advance.

I'm creating a BinaryTree class with templates and an embedded iterator. Here's the relevant lines of what I'm doing:

//in BinTree.h:

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template<class T>
class BinTree{
        struct Node{
        ...
        } *rootNode;
        ...
public:
        BinTree(const T&);
        ~BinTree();
        class iterator;
        friend class iterator;
        class iterator{
                BinTree::Node& node;
                public:
                iterator(const Node&);
                ...
        };
        iterator root();
        ...
};


//in BinTree.cpp:
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#include "BinTree.h"
...

template<class T>
BinTree<T>::iterator BinTree<T>::root(){
    return iterator(*rootNode);
}
...


the compiler complains about the function definition, saying:
error: expected constructor, destructor, or type conversion before 'BinTree'

guestgulkan (2942)
You need to make use of the typename keyword

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template<class T>
class BinTree{
        struct Node{
        ...
        } *rootNode;
        ...
public:
        BinTree(const T&);
        ~BinTree();
        class iterator;
        friend class iterator;
        class iterator{
                typename BinTree::Node& node; //Here *****************
                public:
                iterator(const Node&);
                ...
        };
        iterator root();
        ...
};



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#include "BinTree.h"
...

template<class T>
typename BinTree<T>::iterator BinTree<T>::root(){ //and here *********
    return iterator(*rootNode);
}
...
obice (5)
thanks a lot guestgulkan! that was it.
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