boost/array.hpp
#ifndef BOOST_ARRAY_HPP_INCLUDED #define BOOST_ARRAY_HPP_INCLUDED /* The following code declares class array, * an STL container (as wrapper) for arrays of constant size. * * See * http://www.boost.org/libs/array/ * for documentation. * * The original author site is at: http://www.josuttis.com/ * * (C) Copyright Nicolai M. Josuttis 2001. * * 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) * * 9 Jan 2013 - (mtc) Added constexpr * 14 Apr 2012 - (mtc) Added support for boost::hash * 28 Dec 2010 - (mtc) Added cbegin and cend (and crbegin and crend) for C++Ox compatibility. * 10 Mar 2010 - (mtc) fill method added, matching resolution of the standard library working group. * See <http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#776> or Trac issue #3168 * Eventually, we should remove "assign" which is now a synonym for "fill" (Marshall Clow) * 10 Mar 2010 - added workaround for SUNCC and !STLPort [trac #3893] (Marshall Clow) * 29 Jan 2004 - c_array() added, BOOST_NO_PRIVATE_IN_AGGREGATE removed (Nico Josuttis) * 23 Aug 2002 - fix for Non-MSVC compilers combined with MSVC libraries. * 05 Aug 2001 - minor update (Nico Josuttis) * 20 Jan 2001 - STLport fix (Beman Dawes) * 29 Sep 2000 - Initial Revision (Nico Josuttis) * * Jan 29, 2004 */ #include <boost/config.hpp> #include <boost/config/workaround.hpp> #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) # pragma warning(push) # pragma warning(disable: 4510) // boost::array<T,N>' : default constructor could not be generated # pragma warning(disable: 4512) // boost::array<T,N>' : assignment operator could not be generated # pragma warning(disable: 4610) // class 'boost::array<T,N>' can never be instantiated - user defined constructor required # pragma warning(disable: 4702) // unreachable code #endif #include <boost/assert.hpp> #include <boost/static_assert.hpp> #include <boost/throw_exception.hpp> #include <iterator> #include <stdexcept> #include <utility> #include <cstddef> #if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201907L # if __has_include(<compare>) # include <compare> # endif #endif 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 BOOST_CXX14_CONSTEXPR iterator begin() BOOST_NOEXCEPT { return elems; } BOOST_CONSTEXPR const_iterator begin() const BOOST_NOEXCEPT { return elems; } BOOST_CONSTEXPR const_iterator cbegin() const BOOST_NOEXCEPT { return elems; } BOOST_CXX14_CONSTEXPR iterator end() BOOST_NOEXCEPT { return elems+N; } BOOST_CONSTEXPR const_iterator end() const BOOST_NOEXCEPT { return elems+N; } BOOST_CONSTEXPR const_iterator cend() const BOOST_NOEXCEPT { 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() BOOST_NOEXCEPT { return reverse_iterator(end()); } const_reverse_iterator rbegin() const BOOST_NOEXCEPT { return const_reverse_iterator(end()); } const_reverse_iterator crbegin() const BOOST_NOEXCEPT { return const_reverse_iterator(end()); } reverse_iterator rend() BOOST_NOEXCEPT { return reverse_iterator(begin()); } const_reverse_iterator rend() const BOOST_NOEXCEPT { return const_reverse_iterator(begin()); } const_reverse_iterator crend() const BOOST_NOEXCEPT { return const_reverse_iterator(begin()); } // operator[] BOOST_CXX14_CONSTEXPR reference operator[](size_type i) { return BOOST_ASSERT_MSG( i < N, "out of range" ), elems[i]; } #if !BOOST_WORKAROUND(BOOST_GCC, < 50000) BOOST_CONSTEXPR #endif const_reference operator[](size_type i) const { return BOOST_ASSERT_MSG( i < N, "out of range" ), elems[i]; } // at() with range check BOOST_CXX14_CONSTEXPR reference at(size_type i) { return rangecheck(i), elems[i]; } BOOST_CONSTEXPR const_reference at(size_type i) const { return rangecheck(i), elems[i]; } // front() and back() BOOST_CXX14_CONSTEXPR reference front() { return elems[0]; } BOOST_CONSTEXPR const_reference front() const { return elems[0]; } BOOST_CXX14_CONSTEXPR reference back() { return elems[N-1]; } BOOST_CONSTEXPR const_reference back() const { return elems[N-1]; } // size is constant static BOOST_CONSTEXPR size_type size() BOOST_NOEXCEPT { return N; } static BOOST_CONSTEXPR bool empty() BOOST_NOEXCEPT { return false; } static BOOST_CONSTEXPR size_type max_size() BOOST_NOEXCEPT { return N; } enum { static_size = N }; // swap (note: linear complexity) BOOST_CXX14_CONSTEXPR void swap (array<T,N>& y) { std::swap( elems, y.elems ); } // direct access to data BOOST_CONSTEXPR const T* data() const BOOST_NOEXCEPT { return elems; } BOOST_CXX14_CONSTEXPR T* data() BOOST_NOEXCEPT { return elems; } // obsolete BOOST_DEPRECATED( "please use `data()` instead" ) T* c_array() BOOST_NOEXCEPT { return elems; } // assignment with type conversion template <typename T2> array<T,N>& operator= (const array<T2,N>& rhs) { for( std::size_t i = 0; i < N; ++i ) { elems[ i ] = rhs.elems[ i ]; } return *this; } // fill with one value BOOST_CXX14_CONSTEXPR void fill (const T& value) { // using elems[ 0 ] as a temporary copy // avoids the aliasing opportunity betw. // `value` and `elems` elems[ 0 ] = value; for( std::size_t i = 1; i < N; ++i ) { elems[ i ] = elems[ 0 ]; } } // an obsolete synonym for fill BOOST_DEPRECATED( "please use `fill` instead" ) void assign (const T& value) { fill ( value ); } // check range (may be private because it is static) static BOOST_CONSTEXPR bool rangecheck (size_type i) { return i >= size() ? boost::throw_exception(std::out_of_range ("array<>: index out of range")), true : true; } }; template< class T > class array< T, 0 > { public: struct {} elems; // enables initialization with = {{}} 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 BOOST_CXX14_CONSTEXPR iterator begin() BOOST_NOEXCEPT { return data(); } BOOST_CONSTEXPR const_iterator begin() const BOOST_NOEXCEPT { return data(); } BOOST_CONSTEXPR const_iterator cbegin() const BOOST_NOEXCEPT { return data(); } BOOST_CXX14_CONSTEXPR iterator end() BOOST_NOEXCEPT { return begin(); } BOOST_CONSTEXPR const_iterator end() const BOOST_NOEXCEPT { return begin(); } BOOST_CONSTEXPR const_iterator cend() const BOOST_NOEXCEPT { return cbegin(); } // reverse iterator support typedef std::reverse_iterator<iterator> reverse_iterator; typedef std::reverse_iterator<const_iterator> const_reverse_iterator; reverse_iterator rbegin() BOOST_NOEXCEPT { return reverse_iterator(end()); } const_reverse_iterator rbegin() const BOOST_NOEXCEPT { return const_reverse_iterator(end()); } const_reverse_iterator crbegin() const BOOST_NOEXCEPT { return const_reverse_iterator(end()); } reverse_iterator rend() BOOST_NOEXCEPT { return reverse_iterator(begin()); } const_reverse_iterator rend() const BOOST_NOEXCEPT { return const_reverse_iterator(begin()); } const_reverse_iterator crend() const BOOST_NOEXCEPT { return const_reverse_iterator(begin()); } // operator[] reference operator[](size_type /*i*/) { return failed_rangecheck(); } const_reference operator[](size_type /*i*/) const { return failed_rangecheck(); } // at() with range check reference at(size_type /*i*/) { return failed_rangecheck(); } const_reference at(size_type /*i*/) const { return failed_rangecheck(); } // front() and back() reference front() { return failed_rangecheck(); } const_reference front() const { return failed_rangecheck(); } reference back() { return failed_rangecheck(); } const_reference back() const { return failed_rangecheck(); } // size is constant static BOOST_CONSTEXPR size_type size() BOOST_NOEXCEPT { return 0; } static BOOST_CONSTEXPR bool empty() BOOST_NOEXCEPT { return true; } static BOOST_CONSTEXPR size_type max_size() BOOST_NOEXCEPT { return 0; } enum { static_size = 0 }; BOOST_CXX14_CONSTEXPR void swap (array<T,0>& /*y*/) { } // direct access to data BOOST_CONSTEXPR const T* data() const BOOST_NOEXCEPT { return 0; } BOOST_CXX14_CONSTEXPR T* data() BOOST_NOEXCEPT { return 0; } // obsolete BOOST_DEPRECATED( "please use `data()` instead" ) T* c_array() BOOST_NOEXCEPT { return 0; } // assignment with type conversion template <typename T2> array<T,0>& operator= (const array<T2,0>& ) { return *this; } // an obsolete synonym for fill BOOST_DEPRECATED( "please use `fill` instead" ) void assign (const T& value) { fill ( value ); } // fill with one value BOOST_CXX14_CONSTEXPR void fill (const T& ) {} // check range (may be private because it is static) static reference failed_rangecheck () { boost::throw_exception( std::out_of_range( "attempt to access element of an empty array" ) ); } }; // comparisons template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR bool operator== (const array<T,N>& x, const array<T,N>& y) { for( std::size_t i = 0; i < N; ++i ) { if( !( x[ i ] == y[ i ] ) ) return false; } return true; } #if BOOST_WORKAROUND(BOOST_GCC, < 90000) template<class T> BOOST_CXX14_CONSTEXPR bool operator== (const array<T, 0>& /*x*/, const array<T, 0>& /*y*/) { return true; } #endif template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR bool operator!= (const array<T,N>& x, const array<T,N>& y) { return !(x==y); } template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR bool operator< (const array<T,N>& x, const array<T,N>& y) { for( std::size_t i = 0; i < N; ++i ) { if( x[ i ] < y[ i ] ) return true; if( y[ i ] < x[ i ] ) return false; } return false; } #if BOOST_WORKAROUND(BOOST_GCC, < 90000) template<class T> BOOST_CXX14_CONSTEXPR bool operator< (const array<T, 0>& /*x*/, const array<T, 0>& /*y*/) { return false; } #endif template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR bool operator> (const array<T,N>& x, const array<T,N>& y) { return y<x; } template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR bool operator<= (const array<T,N>& x, const array<T,N>& y) { return !(y<x); } template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR bool operator>= (const array<T,N>& x, const array<T,N>& y) { return !(x<y); } // global swap() template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR inline void swap (array<T,N>& x, array<T,N>& y) { x.swap(y); } #if defined(__cpp_impl_three_way_comparison) && __cpp_impl_three_way_comparison >= 201907L # if __has_include(<compare>) template<class T, std::size_t N> constexpr auto operator<=> (const array<T,N>& x, const array<T,N>& y) -> decltype( x.elems[ 0 ] <=> y.elems[ 0 ] ) { for( std::size_t i = 0; i < N; ++i ) { auto r = x.elems[ i ] <=> y.elems[ i ]; if( r != 0 ) return r; } return std::strong_ordering::equal; } template<class T> constexpr auto operator<=> (const array<T,0>& /*x*/, const array<T,0>& /*y*/) -> std::strong_ordering { return std::strong_ordering::equal; } # endif #endif // undocumented and obsolete template <typename T, std::size_t N> BOOST_DEPRECATED( "please use `elems` instead" ) T(&get_c_array(boost::array<T,N>& arg))[N] { return arg.elems; } // Const version. template <typename T, std::size_t N> BOOST_DEPRECATED( "please use `elems` instead" ) const T(&get_c_array(const boost::array<T,N>& arg))[N] { return arg.elems; } template <size_t Idx, typename T, size_t N> BOOST_CXX14_CONSTEXPR T &get(boost::array<T,N> &arr) BOOST_NOEXCEPT { BOOST_STATIC_ASSERT_MSG ( Idx < N, "boost::get<>(boost::array &) index out of range" ); return arr[Idx]; } template <size_t Idx, typename T, size_t N> BOOST_CONSTEXPR const T &get(const boost::array<T,N> &arr) BOOST_NOEXCEPT { BOOST_STATIC_ASSERT_MSG ( Idx < N, "boost::get<>(const boost::array &) index out of range" ); return arr[Idx]; } template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR array<T, N> to_array( T const (&a)[ N ] ) { array<T, N> r = {}; for( std::size_t i = 0; i < N; ++i ) { r[ i ] = a[ i ]; } return r; } #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR array<T, N> to_array( T (&&a)[ N ] ) { array<T, N> r = {}; for( std::size_t i = 0; i < N; ++i ) { r[ i ] = std::move( a[ i ] ); } return r; } template<class T, std::size_t N> BOOST_CXX14_CONSTEXPR array<T, N> to_array( T const (&&a)[ N ] ) { array<T, N> r = {}; for( std::size_t i = 0; i < N; ++i ) { r[ i ] = a[ i ]; } return r; } #endif } /* namespace boost */ #ifndef BOOST_NO_CXX11_HDR_ARRAY // If we don't have std::array, I'm assuming that we don't have std::get namespace std { template <size_t Idx, typename T, size_t N> BOOST_DEPRECATED( "please use `boost::get` instead" ) T &get(boost::array<T,N> &arr) BOOST_NOEXCEPT { BOOST_STATIC_ASSERT_MSG ( Idx < N, "std::get<>(boost::array &) index out of range" ); return arr[Idx]; } template <size_t Idx, typename T, size_t N> BOOST_DEPRECATED( "please use `boost::get` instead" ) const T &get(const boost::array<T,N> &arr) BOOST_NOEXCEPT { BOOST_STATIC_ASSERT_MSG ( Idx < N, "std::get<>(const boost::array &) index out of range" ); return arr[Idx]; } } #endif #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) # pragma warning(pop) #endif #endif // #ifndef BOOST_ARRAY_HPP_INCLUDED