1 #ifndef DATE_DURATION_OPERATORS_HPP___
2 #define DATE_DURATION_OPERATORS_HPP___
3 
4 /* Copyright (c) 2004 CrystalClear Software, Inc.
5  * Subject to the Boost Software License, Version 1.0.
6  * (See accompanying file LICENSE_1_0.txt or
7  * http://www.boost.org/LICENSE_1_0.txt)
8  * Author: Jeff Garland, Bart Garst
9  * $Date$
10  */
11 
12 #include "boost/date_time/gregorian/greg_duration_types.hpp"
13 #include "boost/date_time/posix_time/ptime.hpp"
14 
15 namespace boost {
16 namespace posix_time {
17 
18   /*!@file date_duration_operators.hpp Operators for ptime and
19    * optional gregorian types. Operators use snap-to-end-of-month behavior.
20    * Further details on this behavior can be found in reference for
21    * date_time/date_duration_types.hpp and documentation for
22    * month and year iterators.
23    */
24 
25 
26   /*! Adds a months object and a ptime. Result will be same
27    * day-of-month as ptime unless original day was the last day of month.
28    * see date_time::months_duration for more details */
29   inline BOOST_CXX14_CONSTEXPR
30   ptime
operator +(const ptime & t,const boost::gregorian::months & m)31   operator+(const ptime& t, const boost::gregorian::months& m)
32   {
33     return t + m.get_offset(t.date());
34   }
35 
36   /*! Adds a months object to a ptime. Result will be same
37    * day-of-month as ptime unless original day was the last day of month.
38    * see date_time::months_duration for more details */
39   inline BOOST_CXX14_CONSTEXPR
40   ptime
operator +=(ptime & t,const boost::gregorian::months & m)41   operator+=(ptime& t, const boost::gregorian::months& m)
42   {
43     // get_neg_offset returns a negative duration, so we add
44     return t += m.get_offset(t.date());
45   }
46 
47   /*! Subtracts a months object and a ptime. Result will be same
48    * day-of-month as ptime unless original day was the last day of month.
49    * see date_time::months_duration for more details */
50   inline BOOST_CXX14_CONSTEXPR
51   ptime
operator -(const ptime & t,const boost::gregorian::months & m)52   operator-(const ptime& t, const boost::gregorian::months& m)
53   {
54     // get_neg_offset returns a negative duration, so we add
55     return t + m.get_neg_offset(t.date());
56   }
57 
58   /*! Subtracts a months object from a ptime. Result will be same
59    * day-of-month as ptime unless original day was the last day of month.
60    * see date_time::months_duration for more details */
61   inline BOOST_CXX14_CONSTEXPR
62   ptime
operator -=(ptime & t,const boost::gregorian::months & m)63   operator-=(ptime& t, const boost::gregorian::months& m)
64   {
65     return t += m.get_neg_offset(t.date());
66   }
67 
68   // ptime & years
69 
70   /*! Adds a years object and a ptime. Result will be same
71    * month and day-of-month as ptime unless original day was the
72    * last day of month. see date_time::years_duration for more details */
73   inline BOOST_CXX14_CONSTEXPR
74   ptime
operator +(const ptime & t,const boost::gregorian::years & y)75   operator+(const ptime& t, const boost::gregorian::years& y)
76   {
77     return t + y.get_offset(t.date());
78   }
79 
80   /*! Adds a years object to a ptime. Result will be same
81    * month and day-of-month as ptime unless original day was the
82    * last day of month. see date_time::years_duration for more details */
83   inline BOOST_CXX14_CONSTEXPR
84   ptime
operator +=(ptime & t,const boost::gregorian::years & y)85   operator+=(ptime& t, const boost::gregorian::years& y)
86   {
87     return t += y.get_offset(t.date());
88   }
89 
90   /*! Subtracts a years object and a ptime. Result will be same
91    * month and day-of-month as ptime unless original day was the
92    * last day of month. see date_time::years_duration for more details */
93   inline BOOST_CXX14_CONSTEXPR
94   ptime
operator -(const ptime & t,const boost::gregorian::years & y)95   operator-(const ptime& t, const boost::gregorian::years& y)
96   {
97     // get_neg_offset returns a negative duration, so we add
98     return t + y.get_neg_offset(t.date());
99   }
100 
101   /*! Subtracts a years object from a ptime. Result will be same
102    * month and day-of-month as ptime unless original day was the
103    * last day of month. see date_time::years_duration for more details */
104   inline BOOST_CXX14_CONSTEXPR
105   ptime
operator -=(ptime & t,const boost::gregorian::years & y)106   operator-=(ptime& t, const boost::gregorian::years& y)
107   {
108     // get_neg_offset returns a negative duration, so we add
109     return t += y.get_neg_offset(t.date());
110   }
111 
112 }} // namespaces
113 
114 #endif // DATE_DURATION_OPERATORS_HPP___
115