UNPKG

boost-react-native-bundle

Version:

Boost library as in https://sourceforge.net/projects/boost/files/boost/1.57.0/

114 lines (101 loc) 5.09 kB
<?xml version="1.0" encoding="utf-8"?> <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN" "../../../tools/boostbook/dtd/boostbook.dtd"> <!-- Copyright (c) 2001-2005 CrystalClear Software, Inc. 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) --> <section id="date_time.gregorian.date_iterators"> <title>Date Iterators</title> <link linkend="iterators_intro">Introduction</link> -- <link linkend="iterators_header">Header</link> -- <link linkend="iterators_overview">Overview</link> <anchor id="iterators_intro" /> <bridgehead renderas="sect3">Introduction</bridgehead> <para> Date iterators provide a standard mechanism for iteration through dates. Date iterators are a model of <ulink url="http://www.sgi.com/tech/stl/BidirectionalIterator.html">Bidirectional Iterator</ulink> and can be used to populate collections with dates and other date generation tasks. For example, the <link linkend="date_time.examples.print_month">print month</link> example iterates through all the days in a month and prints them. </para> <para> All of the iterators here derive from boost::gregorian::date_iterator. </para> <anchor id="iterators_header" /> <bridgehead renderas="sect3">Header</bridgehead> <para> <programlisting>#include "boost/date_time/gregorian/gregorian.hpp" //include all types plus i/o or #include "boost/date_time/gregorian/gregorian_types.hpp" //no i/o just types</programlisting> </para> <anchor id="iterators_overview" /> <bridgehead renderas="sect3">Overview</bridgehead> <informaltable frame="all"> <tgroup cols="2"> <thead> <row> <entry valign="top" morerows="1">Syntax</entry> <entry>Description</entry> </row> <row> <entry>Example</entry> </row> </thead> <tbody> <row> <entry valign="top" morerows="1"><screen>date_iterator</screen></entry> <entry>Common (abstract) base class for all day level iterators.</entry> </row> <row> <entry><screen></screen></entry> </row> <row> <entry valign="top" morerows="1"><screen>day_iterator(date start_date, int day_count=1)</screen></entry> <entry>Iterate <code>day_count</code> days at a time. This iterator does not provide postfix increment/decrement operators. Only prefix operators are provided.</entry> </row> <row> <entry><screen>day_iterator day_itr(date(2005,Jan,1)); ++d_itr; // 2005-Jan-02 day_iterator 2day_itr(date(2005,Feb,1),2); ++2d_itr; // 2005-Feb-03</screen></entry> </row> <row> <entry valign="top" morerows="1"><screen>week_iterator(...) Parameters: date start_date int week_offset (defaults to 1)</screen></entry> <entry>Iterate <code>week_offset</code> weeks at a time. This iterator does not provide postfix increment/decrement operators. Only prefix operators are provided.</entry> </row> <row> <entry><screen>week_iterator wk_itr(date(2005,Jan,1)); ++wk_itr; // 2005-Jan-08 week_iterator 2wk_itr(date(2005,Jan,1),2); ++2wk_itr; // 2005-Feb-15</screen></entry> </row> <row> <entry valign="top" morerows="1"><screen>month_iterator(...) Parameters: date start_date int month_offset (defaults to 1)</screen></entry> <entry>Iterate <code>month_offset</code> months. There are special rules for handling the end of the month. These are: if start date is last day of the month, always adjust to last day of the month. If date is beyond the end of the month (e.g. Jan 31 + 1 month) adjust back to end of month (for more details and examples of this, see <link linkend="snap_to_details">Reversibility of Operations Pitfall</link>. <emphasis role="strong">NOTE:</emphasis> the <code>month_iterator</code> is not effected by this pitfall.) This iterator does not provide postfix increment/decrement operators. Only prefix operators are provided.</entry> </row> <row> <entry><screen>month_iterator m_itr(date(2005,Jan,1)); ++m_itr; // 2005-Feb-01 month_iterator 2m_itr(date(2005,Feb,1),2); ++2m_itr; // 2005-Apr-01</screen></entry> </row> <row> <entry valign="top" morerows="1"><screen>year_iterator(...) Parameters: date start_date int year_offset (defaults to 1)</screen></entry> <entry>Iterate year_offset years. The year_iterator will always land on the day of the date parameter except when date is Feb 28 in a non-leap year. In this case the iterator will return Feb 29 for leap years (eg: 2003-Feb-28, 2004-Feb-29, 2005-Feb-28). This iterator does not provide postfix increment/decrement operators. Only prefix operators are provided.</entry> </row> <row> <entry><screen>year_iterator y_itr(date(2005,Jan,1)); ++y_itr; // 2006-Jan-01 year_iterator 2y_itr(date(2005,Feb,1),2); ++2y_itr; // 2007-Feb-01</screen></entry> </row> </tbody> </tgroup> </informaltable> </section>