source: source/ariba/overlay/modules/chord/detail/comparators.hpp@ 3695

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// [License]
#ifndef COMPARATORS_HPP_
#define COMPARATORS_HPP_

/**
 * TODO: Doc
 *
 * @author Sebastian Mies <mies@tm.uka.de>
 */
#include "distances.hpp"

namespace comparators {

using namespace distances;

/// default compare operation
struct default_compare {
        template<typename T>
        int operator ()(const T& x, const T& y) {
                return x == y ? 0 : (x < y ? -1 : 1);
        }
};

/// compares distances to a given center point
template<class CenterType, class T, class Distance = default_distance,
                class Compare = default_compare>
class distance_compare {
private:
        CenterType center;
        Distance distance;
        Compare compare;

public:
        explicit distance_compare(CenterType center,
                        Distance distance = Distance(), Compare compare = Compare()) :
                center(center), distance(distance), compare(compare) {
        }

        const CenterType get_center() const {
                return center;
        }

        int operator ()(const T& x, const T& y) {
                return compare(distance(center, x), distance(center, y));
        }
};

}

#endif /* COMPARATORS_HPP_ */