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Custom interval

Example custom interval demonstrates how to use interval containers with an own interval class type.

#include <iostream>
#include <boost/icl/interval_set.hpp>

using namespace std;
using namespace boost::icl;

// Here is a typical class that may model intervals in your application.
class MyInterval
{
public:
    MyInterval(): _first(), _past(){}
    MyInterval(int lo, int up): _first(lo), _past(up){}
    int first()const{ return _first; }
    int past ()const{ return _past; }
private:
    int _first, _past;
};

namespace boost{ namespace icl 
{
// Class template interval_traits serves as adapter to register and customize your interval class
template<>
struct interval_traits< MyInterval >       //1.  Partially specialize interval_traits for 
{                                          //    your class MyInterval
                                           //2.  Define associated types
    typedef MyInterval     interval_type;  //2.1 MyInterval will be the interval_type
    typedef int            domain_type;    //2.2 The elements of the domain are ints 
    typedef std::less<int> domain_compare; //2.3 This is the way our element shall be ordered.
                                           //3.  Next we define the essential functions 
                                           //    of the specialisation
                                           //3.1 Construction of intervals
    static interval_type construct(const domain_type& lo, const domain_type& up) 
    { return interval_type(lo, up); }        
                                           //3.2 Selection of values 
    static domain_type lower(const interval_type& inter_val){ return inter_val.first(); };
    static domain_type upper(const interval_type& inter_val){ return inter_val.past(); };
};

template<>
struct interval_bound_type<MyInterval>     //4.  Finally we define the interval borders.
{                                          //    Choose between static_open         (lo..up)
    typedef interval_bound_type type;      //                   static_left_open    (lo..up]
    BOOST_STATIC_CONSTANT(bound_type, value = interval_bounds::static_right_open);//[lo..up)
};                                         //               and static_closed       [lo..up] 

}} // namespace boost icl

void custom_interval()
{
    // Now we can use class MyInterval with interval containers:
    typedef interval_set<int, std::less, MyInterval> MyIntervalSet;
    MyIntervalSet mySet;
    mySet += MyInterval(1,9);
    cout << mySet << endl;
    mySet.subtract(3) -= 6;
    cout << mySet << "            subtracted 3 and 6\n";
    mySet ^= MyInterval(2,8);
    cout << mySet <<      "  flipped between 2 and 7\n";
}


int main()
{
    cout << ">>Interval Container Library: Sample custom_interval.cpp <<\n";
    cout << "-----------------------------------------------------------\n";
    cout << "This program uses a user defined interval class:\n";
    custom_interval();
    return 0;
}

// Program output:
/*-----------------------------------------------------------------------------
>>Interval Container Library: Sample custom_interval.cpp <<
-----------------------------------------------------------
This program uses a user defined interval class:
{[1,                      9)}
{[1,  3)   [4,  6)   [7,  9)}       subtracted 3 and 6
{[1,2) [3,4)     [6,7) [8,9)}  flipped between 2 and 7
-----------------------------------------------------------------------------*/


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