functioniterator.h

#ifndef FUNCTIONITERATOR_H
#define FUNCTIONITERATOR_H

#include <iterator>
#include <stack>

namespace afl
{
    class Function;

    class FunctionIterator 
        : public std::iterator<std::bidirectional_iterator_tag, Function*>
    {
        public:
            typedef Function* pointer;
            typedef Function& reference;

            FunctionIterator( Function* begin );

            FunctionIterator operator++( int );

            FunctionIterator operator--( int );

            FunctionIterator& operator++(  );

            FunctionIterator& operator--( );

            bool operator== ( const FunctionIterator& toCompare ) const
                { return (_curFn.size() == 0 && toCompare._curFn.size() == 0) ||
                    (_curFn.size() && toCompare._curFn.size() && 
                     _curFn.top() == toCompare._curFn.top());
                }

            bool operator!= ( const FunctionIterator& toCompare ) const 
                { return ! (*this == toCompare); }

            reference operator*(  );

            pointer operator->(  );

        private:
            std::stack<Function*> _curFn;

            std::stack<size_t>    _curArg;

            void goUpRight(  );

            void goLeftDown(  );
    };
}

#endif // FUNCTIONITERATOR_H

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