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boost/heap/heap_concepts.hpp

// boost heap: concepts
//
// Copyright (C) 2010 Tim Blechmann
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

#ifndef BOOST_HEAP_CONCEPTS_HPP
#define BOOST_HEAP_CONCEPTS_HPP

#include <boost/concept_check.hpp>

namespace boost {
namespace heap  {


template <class C>
struct PriorityQueue:
    boost::ForwardContainer<C>
{
    typedef typename C::iterator iterator;
    typedef typename C::const_iterator const_iterator;
    typedef typename C::allocator_type allocator_type;
    typedef typename C::value_compare value_compare;
    typedef typename C::value_type value_type;
    typedef typename C::const_reference const_reference;


    BOOST_CONCEPT_USAGE(PriorityQueue)
    {
        BOOST_CONCEPT_ASSERT((boost::Assignable<value_type>));
        BOOST_CONCEPT_ASSERT((boost::Container<C>));
        BOOST_CONCEPT_ASSERT((boost::EqualityComparable<C>));
        BOOST_CONCEPT_ASSERT((boost::Comparable<C>));

        BOOST_CONCEPT_ASSERT((boost::Const_BinaryPredicate<value_compare, value_type, value_type>));

        c.swap(c2);
        c.clear();
        a = c.get_allocator();

        typename PriorityQueue::value_type v;
        c.push(v);

        v = c.top();
        c.pop();

        cmp = c.value_comp();

        // verify tags
        has_ordered_iterators = C::has_ordered_iterators;
        is_mergable = C::is_mergable;
        is_stable   = C::is_stable;
    }

private:
    C c, c2;
    allocator_type a;
    typename C::value_type v;
    value_compare cmp;
    bool has_ordered_iterators, is_mergable, is_stable;
};

template <class C>
struct MergablePriorityQueue:
    PriorityQueue<C>
{
    BOOST_CONCEPT_USAGE(MergablePriorityQueue)
    {
        C c, c2;
        c.merge(c2);
    }
};


template <class C>
struct MutablePriorityQueue:
    PriorityQueue<C>
{
    typedef typename C::handle_type handle_type;

    BOOST_CONCEPT_USAGE(MutablePriorityQueue)
    {
        BOOST_CONCEPT_ASSERT((boost::Assignable<typename MutablePriorityQueue::handle_type>));

        typename MutablePriorityQueue::value_type v;
        typename MutablePriorityQueue::handle_type h = c.push(v);
        c.update(h, v);
        c.increase(h, v);
        c.decrease(h, v);

        c.update(h);
        c.increase(h);
        c.decrease(h);
    }

    C c;
};

}}

#endif /* BOOST_HEAP_CONCEPTS_HPP */