// Money.h

#ifndef MONEY_H

#define MONEY_H

#include <string>

#include <stdexcept>

#include <cppunit/portability/Stream.h>    // or <iostream> if portability is not an issue

class IncompatibleMoneyError : public std::runtime_error

{

public:

   IncompatibleMoneyError() : std::runtime_error( "Incompatible moneys" )

  {

  }

};

class Money

{

public:

  Money( double amount, std::string currency )

    : m_amount( amount )

    , m_currency( currency )

  {

  }

  double getAmount() const

  {

    return m_amount;

  }

  std::string getCurrency() const

  {

    return m_currency;

  }

  bool operator ==( const Money &other ) const

  {

    return m_amount == other.m_amount  &&  

           m_currency == other.m_currency;

  }

  bool operator !=( const Money &other ) const

  {

    return !(*this == other);

  }

  Money &operator +=( const Money &other )

  {

    if ( m_currency != other.m_currency )

      throw IncompatibleMoneyError();

    m_amount += other.m_amount;

    return *this;

  }

private:

  double m_amount;

  std::string m_currency;

};

// The function below could be prototyped as:

// inline std::ostream &operator <<( std::ostream &os, const Money &value )

// If you know that you will never compile on a platform without std::ostream

// (such as embedded vc++ 4.0; though even that platform you can use STLPort)

inline CPPUNIT_NS::OStream &operator <<( CPPUNIT_NS::OStream &os, const Money &value )

{

    return os << "Money< value =" << value.getAmount() << "; currency = " << value.getCurrency() << ">";

}

#endif