date_time/xmldoc/usage_examples.xml

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     Subject to the Boost Software License, Version 1.0. 
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<section id="date_time.examples.general_usage_examples">
  <title>General Usage Examples</title>

  <para>
    The following provides some sample usage of dates.
    See <link linkend="date_time.gregorian">Date Programming</link> 
    for more details.

    <programlisting>using namespace boost::gregorian; 
    date weekstart(2002,Feb,1);
    date weekend  = weekstart + week(1);
    date d2 = d1 + days(5);
    date today = day_clock::local_day();
    if (d2 &gt;= today) {} //date comparison operators

    date_period thisWeek(d1,d2);
    if (thisWeek.contains(today)) {}//do something

    //iterate and print the week
    day_iterator itr(weekstart);
    while (itr &lt;= weekend) {
     std::cout &lt;&lt; (*itr) &lt;&lt; std::endl;
     ++itr;
    }  
    //input streaming
    std::stringstream ss("2004-Jan-1");
    ss &gt;&gt; d3;

    //date generator functions
    date d5 = next_weekday(d4, Sunday); //calculate sunday following d4

    //define a shorthand for the 
    // nth_day_of_the_week_in_month function object
    typedef nth_day_of_the_week_in_month nth_dow;
    //US labor day is first Monday in Sept
    nth_dow labor_day(nth_dow::first,Monday, Sep); 
    //calculate a specific date from functor
    date d6 = labor_day.get_date(2004); 
    </programlisting>    

      The following provides some example code using times.
      See <link linkend="date_time.posix_time">Time Programming</link> 
      for more details.

    <programlisting>use namespace boost::posix_time; 
    date d(2002,Feb,1); //an arbitrary date
    ptime t1(d, hours(5)+nanosec(100)); //date + time of day offset
    ptime t2 = t1 - minutes(4)+seconds(2);
    ptime now = second_clock::local_time(); //use the clock
    date today = now.date(); //Get the date part out of the time
    date tommorrow = today + date_duration(1);
    ptime tommorrow_start(tommorrow); //midnight 

    //input streaming
    std::stringstream ss("2004-Jan-1 05:21:33.20");
    ss &gt;&gt; t2;

    //starting at current time iterator adds by one hour
    time_iterator titr(now,hours(1)); 
    for (; titr &lt; tommorrow_start; ++titr) {
     std::cout &lt;&lt; (*titr) &lt;&lt; std::endl;
    }
    </programlisting>    
  </para>
  
</section>