A split_interval_set сохраняет все интервальные границы при вводе и пересечении операций. Таким образом, split_interval_set и добавление интервала

x =  {[1,     3)}
x.add(     [2,     4))

затем интервалы делятся на их границы

x == {[1,2)[2,3)[3,4)}

Используя это свойство, мы можем пересекать split_interval_maps, чтобы итерировать через интервалы учет всех происходящих изменений интервальных границ.

В этом примере мы обеспечиваем пересечение двух split_interval_sets, представляющих месячную и недельную сетку времени.

// The next line includes <boost/gregorian/date.hpp>
// and a few lines of adapter code.
#include <boost/icl/gregorian.hpp>
#include <iostream>
#include <boost/icl/split_interval_set.hpp>
using namespace std;
using namespace boost::gregorian;
using namespace boost::icl;
typedef split_interval_set<boost::gregorian::date> date_grid;
// This function splits a gregorian::date interval 'scope' into a month grid:
// For every month contained in 'scope' that month is contained as interval
// in the resulting split_interval_set.
date_grid month_grid(const discrete_interval<date>& scope)
{
    split_interval_set<date> month_grid;
    date frame_months_1st = first(scope).end_of_month() + days(1) - months(1);
    month_iterator month_iter(frame_months_1st);
    for(; month_iter <= last(scope); ++month_iter)
        month_grid += discrete_interval<date>::right_open(*month_iter, *month_iter + months(1));
    month_grid &= scope; // cut off the surplus
    return month_grid;
}
// This function splits a gregorian::date interval 'scope' into a week grid:
// For every week contained in 'scope' that month is contained as interval
// in the resulting split_interval_set.
date_grid week_grid(const discrete_interval<date>& scope)
{
    split_interval_set<date> week_grid;
    date frame_weeks_1st = first(scope) + days(days_until_weekday(first(scope), greg_weekday(Monday))) - weeks(1);
    week_iterator week_iter(frame_weeks_1st);
    for(; week_iter <= last(scope); ++week_iter)
        week_grid.insert(discrete_interval<date>::right_open(*week_iter, *week_iter + weeks(1)));
    week_grid &= scope; // cut off the surplus
    return week_grid;
}
// For a period of two months, starting from today, the function
// computes a partitioning for months and weeks using intersection
// operator &= on split_interval_sets.
void month_and_time_grid()
{
    date someday = day_clock::local_day();
    date thenday = someday + months(2);
    discrete_interval<date> itv = discrete_interval<date>::right_open(someday, thenday);
    // Compute a month grid
    date_grid month_and_week_grid = month_grid(itv);
    // Intersection of the month and week grids:
    month_and_week_grid &= week_grid(itv);
    cout << "interval : " << first(itv) << " - " << last(itv)
         << " month and week partitions:" << endl;
    cout << "---------------------------------------------------------------\n";
    for(date_grid::iterator it = month_and_week_grid.begin();
        it != month_and_week_grid.end(); it++)
    {
        if(first(*it).day() == 1)
            cout << "new month: ";
        else if(first(*it).day_of_week()==greg_weekday(Monday))
            cout << "new week : " ;
        else if(it == month_and_week_grid.begin())
            cout << "first day: " ;
        cout << first(*it) << " - " << last(*it) << endl;
    }
}
int main()
{
    cout << ">>Interval Container Library: Sample month_and_time_grid.cpp <<\n";
    cout << "---------------------------------------------------------------\n";
    month_and_time_grid();
    return 0;
}
// Program output:
/*
>>Interval Container Library: Sample month_and_time_grid.cpp <<
---------------------------------------------------------------
interval : 2008-Jun-22 - 2008-Aug-21 month and week partitions:
---------------------------------------------------------------
first day: 2008-Jun-22 - 2008-Jun-22
new week : 2008-Jun-23 - 2008-Jun-29
new week : 2008-Jun-30 - 2008-Jun-30
new month: 2008-Jul-01 - 2008-Jul-06
new week : 2008-Jul-07 - 2008-Jul-13
new week : 2008-Jul-14 - 2008-Jul-20
new week : 2008-Jul-21 - 2008-Jul-27
new week : 2008-Jul-28 - 2008-Jul-31
new month: 2008-Aug-01 - 2008-Aug-03
new week : 2008-Aug-04 - 2008-Aug-10
new week : 2008-Aug-11 - 2008-Aug-17
new week : 2008-Aug-18 - 2008-Aug-21
*/