/* The following code declares class array,
 * an STL container (as wrapper) for arrays of constant size.
 *
 * See
 *      http://www.josuttis.com/cppcode
 * for details and the latest version.
 *
 * (C) Copyright Nicolai M. Josuttis 1999.
 * Permission to copy, use, modify, sell and distribute this software
 * is granted provided this copyright notice appears in all copies.
 * This software is provided "as is" without express or implied
 * warranty, and with no claim as to its suitability for any purpose.
 *
 * Jul 31, 2000
 */
#ifndef BOOST_ARRAY_HPP
#define BOOST_ARRAY_HPP

#include <cstddef>
#include <stdexcept>
#include <iterator>
#include <algorithm>

#include <boost/config.hpp> // for std::size_t and std::ptrdiff_t workarounds

namespace boost {

    template<class T, std::size_t N>
    class array {
      public:
        T elems[N];    // fixed-size array of elements of type T

      public:
        // type definitions
        typedef T              value_type;
        typedef T*             iterator;
        typedef const T*       const_iterator;
        typedef T&             reference;
        typedef const T&       const_reference;
        typedef std::size_t    size_type;
        typedef std::ptrdiff_t difference_type;
    
        // iterator support
        iterator begin() { return elems; }
        const_iterator begin() const { return elems; }
        iterator end() { return elems+N; }
        const_iterator end() const { return elems+N; }
    
        // reverse iterator support
        typedef std::reverse_iterator<iterator> reverse_iterator;
        typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
        reverse_iterator rbegin() { return reverse_iterator(end()); }
        const_reverse_iterator rbegin() const {
            return const_reverse_iterator(end());
        }
        reverse_iterator rend() { return reverse_iterator(begin()); }
        const_reverse_iterator rend() const {
            return const_reverse_iterator(begin());
        }

        // operator[]
        reference operator[](size_type i) { return elems[i]; }
        const_reference operator[](size_type i) const { return elems[i]; }

        // at() with range check
        // note: rangecheck() is public because we have implemented array
        //       as aggregate, which forbids non-public members
        void rangecheck (size_type i) const {
            if (i >= size()) { throw std::range_error("array"); }
        }
        reference at(size_type i) { rangecheck(i); return elems[i]; }
        const_reference at(size_type i) const { rangecheck(i); return elems[i]; }
    
        // front() and back()
        reference front() { return elems[0]; }
        const_reference front() const { return elems[0]; }
        reference back() { return elems[N-1]; }
        const_reference back() const { return elems[N-1]; }

        // size is constant
        static size_type size() { return N; }
        static bool empty() { return false; }
        static size_type max_size() { return N; }
        enum { static_size = N };

        // swap (note: linear complexity)
        void swap (array& y) {
            std::swap_ranges(begin(),end(),y.begin());
        }

        // direct access to data
        const T* data() const { return elems; }

        // assignment with type conversion
        //template <typename T2>
        //T& operator= (const array<T2,N>& rhs) {
        //    std::copy (begin(),end(),rhs.begin());
        //}
    };

    // comparisons
    template<class T, std::size_t N>
    bool operator== (const array<T,N>& x, const array<T,N>& y) {
        return std::equal(x.begin(), x.end(), y.begin());
    }
    template<class T, std::size_t N>
    bool operator< (const array<T,N>& x, const array<T,N>& y) {
        return std::lexicographical_compare(x.begin(),x.end(),y.begin(),y.end());
    }
    template<class T, std::size_t N>
    bool operator!= (const array<T,N>& x, const array<T,N>& y) {
        return !(x==y);
    }
    template<class T, std::size_t N>
    bool operator> (const array<T,N>& x, const array<T,N>& y) {
        return y<x;
    }
    template<class T, std::size_t N>
    bool operator<= (const array<T,N>& x, const array<T,N>& y) {
        return !(y<x);
    }
    template<class T, std::size_t N>
    bool operator>= (const array<T,N>& x, const array<T,N>& y) {
        return !(x<y);
    }

    // global swap()
    template<class T, std::size_t N>
    inline void swap (const array<T,N>& x, const array<T,N>& y) {
        x.swap(y);
    }

} /* namespace boost */

#endif /*BOOST_ARRAY_HPP*/