boost/date_time/date_duration.hpp
#ifndef DATE_TIME_DATE_DURATION__
#define DATE_TIME_DATE_DURATION__
/* Copyright (c) 2002,2003 CrystalClear Software, Inc.
* Use, modification and distribution is subject to the
* Boost Software License, Version 1.0. (See accompanying
* file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
* Author: Jeff Garland, Bart Garst
* $Date: 2008-11-12 11:37:53 -0800 (Wed, 12 Nov 2008) $
*/
#include <boost/operators.hpp>
#include <boost/date_time/special_defs.hpp>
namespace boost {
namespace date_time {
//! Duration type with date level resolution
template<class duration_rep_traits>
class date_duration : private
boost::less_than_comparable1< date_duration< duration_rep_traits >
, boost::equality_comparable1< date_duration< duration_rep_traits >
, boost::addable1< date_duration< duration_rep_traits >
, boost::subtractable1< date_duration< duration_rep_traits >
, boost::dividable2< date_duration< duration_rep_traits >, int
> > > > >
{
public:
typedef typename duration_rep_traits::int_type duration_rep_type;
typedef typename duration_rep_traits::impl_type duration_rep;
//! Construct from a day count
explicit date_duration(duration_rep day_count) : days_(day_count) {};
/*! construct from special_values - only works when
* instantiated with duration_traits_adapted */
date_duration(special_values sv) :
days_(duration_rep::from_special(sv))
{}
// copy constructor required for addable<> & subtractable<>
//! Construct from another date_duration (Copy Constructor)
date_duration(const date_duration<duration_rep_traits>& other) :
days_(other.days_)
{}
//! returns days_ as it's instantiated type - used for streaming
duration_rep get_rep()const
{
return days_;
}
bool is_special()const
{
return days_.is_special();
}
//! returns days as value, not object.
duration_rep_type days() const
{
return duration_rep_traits::as_number(days_);
}
//! Returns the smallest duration -- used by to calculate 'end'
static date_duration unit()
{
return date_duration<duration_rep_traits>(1);
}
//! Equality
bool operator==(const date_duration& rhs) const
{
return days_ == rhs.days_;
}
//! Less
bool operator<(const date_duration& rhs) const
{
return days_ < rhs.days_;
}
/* For shortcut operators (+=, -=, etc) simply using
* "days_ += days_" may not work. If instantiated with
* an int_adapter, shortcut operators are not present,
* so this will not compile */
//! Subtract another duration -- result is signed
date_duration& operator-=(const date_duration& rhs)
{
//days_ -= rhs.days_;
days_ = days_ - rhs.days_;
return *this;
}
//! Add a duration -- result is signed
date_duration& operator+=(const date_duration& rhs)
{
days_ = days_ + rhs.days_;
return *this;
}
//! unary- Allows for dd = -date_duration(2); -> dd == -2
date_duration operator-() const
{
return date_duration<duration_rep_traits>(get_rep() * (-1));
}
//! Division operations on a duration with an integer.
date_duration& operator/=(int divisor)
{
days_ = days_ / divisor;
return *this;
}
//! return sign information
bool is_negative() const
{
return days_ < 0;
}
private:
duration_rep days_;
};
/*! Struct for instantiating date_duration with <b>NO</b> special values
* functionality. Allows for transparent implementation of either
* date_duration<long> or date_duration<int_adapter<long> > */
struct duration_traits_long
{
typedef long int_type;
typedef long impl_type;
static int_type as_number(impl_type i) { return i; };
};
/*! Struct for instantiating date_duration <b>WITH</b> special values
* functionality. Allows for transparent implementation of either
* date_duration<long> or date_duration<int_adapter<long> > */
struct duration_traits_adapted
{
typedef long int_type;
typedef boost::date_time::int_adapter<long> impl_type;
static int_type as_number(impl_type i) { return i.as_number(); };
};
} } //namspace date_time
#endif