1#ifndef DATE_ITERATOR_HPP___
2#define DATE_ITERATOR_HPP___
3
4/* Copyright (c) 2002,2003 CrystalClear Software, Inc.
5 * Use, modification and distribution is subject to the
6 * Boost Software License, Version 1.0. (See accompanying
7 * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
8 * Author: Jeff Garland, Bart Garst
9 * $Date$
10 */
11
12#include <iterator>
13
14namespace boost {
15namespace date_time {
16 //! An iterator over dates with varying resolution (day, week, month, year, etc)
17 enum date_resolutions {day, week, months, year, decade, century, NumDateResolutions};
18
19 //! Base date iterator type
20 /*! This class provides the skeleton for the creation of iterators.
21 * New and interesting interators can be created by plugging in a new
22 * function that derives the next value from the current state.
23 * generation of various types of -based information.
24 *
25 * <b>Template Parameters</b>
26 *
27 * <b>date_type</b>
28 *
29 * The date_type is a concrete date_type. The date_type must
30 * define a duration_type and a calendar_type.
31 */
32 template<class date_type>
33 class date_itr_base {
34 // works, but benefit unclear at the moment
35 // class date_itr_base : public std::iterator<std::input_iterator_tag,
36 // date_type, void, void, void>{
37 public:
38 typedef typename date_type::duration_type duration_type;
39 typedef date_type value_type;
40 typedef std::input_iterator_tag iterator_category;
41
42 date_itr_base(date_type d) : current_(d) {}
43 virtual ~date_itr_base() {}
44 date_itr_base& operator++()
45 {
46 current_ = current_ + get_offset(current: current_);
47 return *this;
48 }
49 date_itr_base& operator--()
50 {
51 current_ = current_ + get_neg_offset(current: current_);
52 return *this;
53 }
54 virtual duration_type get_offset(const date_type& current) const=0;
55 virtual duration_type get_neg_offset(const date_type& current) const=0;
56 date_type operator*() {return current_;}
57 date_type* operator->() {return &current_;}
58 bool operator< (const date_type& d) {return current_ < d;}
59 bool operator<= (const date_type& d) {return current_ <= d;}
60 bool operator> (const date_type& d) {return current_ > d;}
61 bool operator>= (const date_type& d) {return current_ >= d;}
62 bool operator== (const date_type& d) {return current_ == d;}
63 bool operator!= (const date_type& d) {return current_ != d;}
64 private:
65 date_type current_;
66 };
67
68 //! Overrides the base date iterator providing hook for functors
69 /*
70 * <b>offset_functor</b>
71 *
72 * The offset functor must define a get_offset function that takes the
73 * current point in time and calculates and offset.
74 *
75 */
76 template<class offset_functor, class date_type>
77 class date_itr : public date_itr_base<date_type> {
78 public:
79 typedef typename date_type::duration_type duration_type;
80 date_itr(date_type d, int factor=1) :
81 date_itr_base<date_type>(d),
82 of_(factor)
83 {}
84 private:
85 virtual duration_type get_offset(const date_type& current) const
86 {
87 return of_.get_offset(current);
88 }
89 virtual duration_type get_neg_offset(const date_type& current) const
90 {
91 return of_.get_neg_offset(current);
92 }
93 offset_functor of_;
94 };
95
96
97
98} } //namespace date_time
99
100
101#endif
102

source code of boost/boost/date_time/date_iterator.hpp