/usr/include/boost/date_time
Edit: /usr/include/boost/date_time/adjust_functors.hpp (5467B)
#ifndef _DATE_TIME_ADJUST_FUNCTORS_HPP___
#define _DATE_TIME_ADJUST_FUNCTORS_HPP___
/* 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
* $Date$
*/
#include "boost/date_time/date.hpp"
#include "boost/date_time/wrapping_int.hpp"
namespace boost {
namespace date_time {
//! Functor to iterate a fixed number of days
template
class day_functor
{
public:
typedef typename date_type::duration_type duration_type;
day_functor(int f) : f_(f) {}
duration_type get_offset(const date_type&) const
{
return duration_type(f_);
}
duration_type get_neg_offset(const date_type&) const
{
return duration_type(-f_);
}
private:
int f_;
};
//! Provides calculation to find next nth month given a date
/*! This adjustment function provides the logic for 'month-based'
* advancement on a ymd based calendar. The policy it uses
* to handle the non existant end of month days is to back
* up to the last day of the month. Also, if the starting
* date is the last day of a month, this functor will attempt
* to adjust to the end of the month.
*/
template
class month_functor
{
public:
typedef typename date_type::duration_type duration_type;
typedef typename date_type::calendar_type cal_type;
typedef typename cal_type::ymd_type ymd_type;
typedef typename cal_type::day_type day_type;
month_functor(int f) : f_(f), origDayOfMonth_(0) {}
duration_type get_offset(const date_type& d) const
{
ymd_type ymd(d.year_month_day());
if (origDayOfMonth_ == 0) {
origDayOfMonth_ = ymd.day;
day_type endOfMonthDay(cal_type::end_of_month_day(ymd.year,ymd.month));
if (endOfMonthDay == ymd.day) {
origDayOfMonth_ = -1; //force the value to the end of month
}
}
typedef date_time::wrapping_int2 wrap_int2;
wrap_int2 wi(ymd.month);
//calc the year wrap around, add() returns 0 or 1 if wrapped
const typename ymd_type::year_type year(static_cast(ymd.year + wi.add(f_)));
// std::cout << "trace wi: " << wi.as_int() << std::endl;
// std::cout << "trace year: " << year << std::endl;
//find the last day for the new month
day_type resultingEndOfMonthDay(cal_type::end_of_month_day(year, wi.as_int()));
//original was the end of month -- force to last day of month
if (origDayOfMonth_ == -1) {
return date_type(year, wi.as_int(), resultingEndOfMonthDay) - d;
}
day_type dayOfMonth = origDayOfMonth_;
if (dayOfMonth > resultingEndOfMonthDay) {
dayOfMonth = resultingEndOfMonthDay;
}
return date_type(year, wi.as_int(), dayOfMonth) - d;
}
//! Returns a negative duration_type
duration_type get_neg_offset(const date_type& d) const
{
ymd_type ymd(d.year_month_day());
if (origDayOfMonth_ == 0) {
origDayOfMonth_ = ymd.day;
day_type endOfMonthDay(cal_type::end_of_month_day(ymd.year,ymd.month));
if (endOfMonthDay == ymd.day) {
origDayOfMonth_ = -1; //force the value to the end of month
}
}
typedef date_time::wrapping_int2 wrap_int2;
wrap_int2 wi(ymd.month);
//calc the year wrap around, add() returns 0 or 1 if wrapped
const typename ymd_type::year_type year(static_cast(ymd.year + wi.subtract(f_)));
//find the last day for the new month
day_type resultingEndOfMonthDay(cal_type::end_of_month_day(year, wi.as_int()));
//original was the end of month -- force to last day of month
if (origDayOfMonth_ == -1) {
return date_type(year, wi.as_int(), resultingEndOfMonthDay) - d;
}
day_type dayOfMonth = origDayOfMonth_;
if (dayOfMonth > resultingEndOfMonthDay) {
dayOfMonth = resultingEndOfMonthDay;
}
return date_type(year, wi.as_int(), dayOfMonth) - d;
}
private:
int f_;
mutable short origDayOfMonth_;
};
//! Functor to iterate a over weeks
template
class week_functor
{
public:
typedef typename date_type::duration_type duration_type;
typedef typename date_type::calendar_type calendar_type;
week_functor(int f) : f_(f) {}
duration_type get_offset(const date_type&) const
{
return duration_type(f_*static_cast(calendar_type::days_in_week()));
}
duration_type get_neg_offset(const date_type&) const
{
return duration_type(-f_*static_cast(calendar_type::days_in_week()));
}
private:
int f_;
};
//! Functor to iterate by a year adjusting for leap years
template
class year_functor
{
public:
//typedef typename date_type::year_type year_type;
typedef typename date_type::duration_type duration_type;
year_functor(int f) : _mf(f * 12) {}
duration_type get_offset(const date_type& d) const
{
return _mf.get_offset(d);
}
duration_type get_neg_offset(const date_type& d) const
{
return _mf.get_neg_offset(d);
}
private:
month_functor _mf;
};
} }//namespace date_time
#endif