STL & Generic Programming: Writing Your Own Iterators

Listing 5: Exposing sequences from the measurements class

public:
  typedef std::vector<std::pair<double, Date> > MeasurementsCollection;
  typedef MeasurementsCollection::const_iterator const_iterator;
  typedef iterator_to_member<
    const_iterator,
    std::pair<double, Date>,
    const double
    > const_value_iterator;

  MeasurementsCollection::size_type size() { 
    return m_vectMeasurements.size(); 
  }
  
  const_iterator begin() { 
    return m_vectMeasurements.begin(); 
  }
  
  const_iterator end() { 
    return m_vectMeasurements.end();  
  }
  
  const_value_iterator value_begin() { 
    return const_value_iterator(
      m_vectMeasurements.begin(),
      &std::pair<double, Date>::first
      );
  }
  
  const_value_iterator value_end() { 
    return const_value_iterator(
      m_vectMeasurements.end(),
      &std::pair<double, Date>::first
      );
  }

private:
  MeasurementsCollection m_vectMeasurements;

— End of Listing —