//  Boost operators.hpp header file  ----------------------------------------//

//  (C) Copyright David Abrahams, Jeremy Siek, Daryle Walker 1999-2001.

//  (C) Copyright Daniel Frey 2002-2017.

//  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)

//  See http://www.boost.org/libs/utility/operators.htm for documentation.

//  Revision History

//  23 Nov 17 Protect dereferenceable<> from overloaded operator&.

//  15 Oct 17 Adapted to C++17, replace std::iterator<> with manual

//            implementation.

//  22 Feb 16 Added ADL protection, preserve old work-arounds in

//            operators_v1.hpp and clean up this file. (Daniel Frey)

//  16 Dec 10 Limit warning suppression for 4284 to older versions of VC++

//            (Matthew Bradbury, fixes #4432)

//  07 Aug 08 Added "euclidean" spelling. (Daniel Frey)

//  03 Apr 08 Make sure "convertible to bool" is sufficient

//            for T::operator<, etc. (Daniel Frey)

//  24 May 07 Changed empty_base to depend on T, see

//            http://svn.boost.org/trac/boost/ticket/979

//  21 Oct 02 Modified implementation of operators to allow compilers with a

//            correct named return value optimization (NRVO) to produce optimal

//            code.  (Daniel Frey)

//  02 Dec 01 Bug fixed in random_access_iteratable.  (Helmut Zeisel)

//  28 Sep 01 Factored out iterator operator groups.  (Daryle Walker)

//  27 Aug 01 'left' form for non commutative operators added;

//            additional classes for groups of related operators added;

//            workaround for empty base class optimization

//            bug of GCC 3.0 (Helmut Zeisel)

//  25 Jun 01 output_iterator_helper changes: removed default template

//            parameters, added support for self-proxying, additional

//            documentation and tests (Aleksey Gurtovoy)

//  29 May 01 Added operator classes for << and >>.  Added input and output

//            iterator helper classes.  Added classes to connect equality and

//            relational operators.  Added classes for groups of related

//            operators.  Reimplemented example operator and iterator helper

//            classes in terms of the new groups.  (Daryle Walker, with help

//            from Alexy Gurtovoy)

//  11 Feb 01 Fixed bugs in the iterator helpers which prevented explicitly

//            supplied arguments from actually being used (Dave Abrahams)

//  04 Jul 00 Fixed NO_OPERATORS_IN_NAMESPACE bugs, major cleanup and

//            refactoring of compiler workarounds, additional documentation

//            (Alexy Gurtovoy and Mark Rodgers with some help and prompting from

//            Dave Abrahams)

//  28 Jun 00 General cleanup and integration of bugfixes from Mark Rodgers and

//            Jeremy Siek (Dave Abrahams)

//  20 Jun 00 Changes to accommodate Borland C++Builder 4 and Borland C++ 5.5

//            (Mark Rodgers)

//  20 Jun 00 Minor fixes to the prior revision (Aleksey Gurtovoy)

//  10 Jun 00 Support for the base class chaining technique was added

//            (Aleksey Gurtovoy). See documentation and the comments below

//            for the details.

//  12 Dec 99 Initial version with iterator operators (Jeremy Siek)

//  18 Nov 99 Change name "divideable" to "dividable", remove unnecessary

//            specializations of dividable, subtractable, modable (Ed Brey)

//  17 Nov 99 Add comments (Beman Dawes)

//            Remove unnecessary specialization of operators<> (Ed Brey)

//  15 Nov 99 Fix less_than_comparable<T,U> second operand type for first two

//            operators.(Beman Dawes)

//  12 Nov 99 Add operators templates (Ed Brey)

//  11 Nov 99 Add single template parameter version for compilers without

//            partial specialization (Beman Dawes)

//  10 Nov 99 Initial version

// 10 Jun 00:

// An additional optional template parameter was added to most of

// operator templates to support the base class chaining technique (see

// documentation for the details). Unfortunately, a straightforward

// implementation of this change would have broken compatibility with the

// previous version of the library by making it impossible to use the same

// template name (e.g. 'addable') for both the 1- and 2-argument versions of

// an operator template. This implementation solves the backward-compatibility

// issue at the cost of some simplicity.

//

// One of the complications is an existence of special auxiliary class template

// 'is_chained_base<>' (see 'operators_detail' namespace below), which is used

// to determine whether its template parameter is a library's operator template

// or not. You have to specialize 'is_chained_base<>' for each new

// operator template you add to the library.

//

// However, most of the non-trivial implementation details are hidden behind

// several local macros defined below, and as soon as you understand them,

// you understand the whole library implementation.

#ifndef BOOST_OPERATORS_HPP

#define BOOST_OPERATORS_HPP

// If old work-arounds are needed, refer to the preserved version without

// ADL protection.

#if defined(BOOST_NO_OPERATORS_IN_NAMESPACE) || defined(BOOST_USE_OPERATORS_V1)

#include "operators_v1.hpp"

#else

#include <cstddef>

#include <iterator>

#include <boost/config.hpp>

#include <boost/detail/workaround.hpp>

#include <boost/core/addressof.hpp>

#if defined(__sgi) && !defined(__GNUC__)

#   pragma set woff 1234

#endif

#if BOOST_WORKAROUND(BOOST_MSVC, < 1600)

#   pragma warning( disable : 4284 ) // complaint about return type of

#endif                               // operator-> not begin a UDT

// In this section we supply the xxxx1 and xxxx2 forms of the operator

// templates, which are explicitly targeted at the 1-type-argument and

// 2-type-argument operator forms, respectively.

namespace boost

{

namespace operators_impl

{

namespace operators_detail

{

template <typename T> class empty_base {};

} // namespace operators_detail

//  Basic operator classes (contributed by Dave Abrahams) ------------------//

//  Note that friend functions defined in a class are implicitly inline.

//  See the C++ std, 11.4 [class.friend] paragraph 5

template <class T, class U, class B = operators_detail::empty_base<T> >

struct less_than_comparable2 : B

{

     friend bool operator<=(const T& x, const U& y) { return !static_cast<bool>(x > y); }

     friend bool operator>=(const T& x, const U& y) { return !static_cast<bool>(x < y); }

     friend bool operator>(const U& x, const T& y)  { return y < x; }

     friend bool operator<(const U& x, const T& y)  { return y > x; }

     friend bool operator<=(const U& x, const T& y) { return !static_cast<bool>(y < x); }

     friend bool operator>=(const U& x, const T& y) { return !static_cast<bool>(y > x); }

};

template <class T, class B = operators_detail::empty_base<T> >

struct less_than_comparable1 : B

{

     friend bool operator>(const T& x, const T& y)  { return y < x; }

     friend bool operator<=(const T& x, const T& y) { return !static_cast<bool>(y < x); }

     friend bool operator>=(const T& x, const T& y) { return !static_cast<bool>(x < y); }

};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct equality_comparable2 : B

{

     friend bool operator==(const U& y, const T& x) { return x == y; }

     friend bool operator!=(const U& y, const T& x) { return !static_cast<bool>(x == y); }

     friend bool operator!=(const T& y, const U& x) { return !static_cast<bool>(y == x); }

};

template <class T, class B = operators_detail::empty_base<T> >

struct equality_comparable1 : B

{

     friend bool operator!=(const T& x, const T& y) { return !static_cast<bool>(x == y); }

};

// A macro which produces "name_2left" from "name".

#define BOOST_OPERATOR2_LEFT(name) name##2##_##left

//  NRVO-friendly implementation (contributed by Daniel Frey) ---------------//

#if defined(BOOST_HAS_NRVO) || defined(BOOST_FORCE_SYMMETRIC_OPERATORS)

// This is the optimal implementation for ISO/ANSI C++,

// but it requires the compiler to implement the NRVO.

// If the compiler has no NRVO, this is the best symmetric

// implementation available.

#define BOOST_BINARY_OPERATOR_COMMUTATIVE( NAME, OP )                   \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct NAME##2 : B                                                      \

{                                                                       \

  friend T operator OP( const T& lhs, const U& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

  friend T operator OP( const U& lhs, const T& rhs )                    \

    { T nrv( rhs ); nrv OP##= lhs; return nrv; }                        \

};                                                                      \

                                                                        \

template <class T, class B = operators_detail::empty_base<T> >          \

struct NAME##1 : B                                                      \

{                                                                       \

  friend T operator OP( const T& lhs, const T& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

};

#define BOOST_BINARY_OPERATOR_NON_COMMUTATIVE( NAME, OP )               \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct NAME##2 : B                                                      \

{                                                                       \

  friend T operator OP( const T& lhs, const U& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

};                                                                      \

                                                                        \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct BOOST_OPERATOR2_LEFT(NAME) : B                                   \

{                                                                       \

  friend T operator OP( const U& lhs, const T& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

};                                                                      \

                                                                        \

template <class T, class B = operators_detail::empty_base<T> >          \

struct NAME##1 : B                                                      \

{                                                                       \

  friend T operator OP( const T& lhs, const T& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

};

#else // defined(BOOST_HAS_NRVO) || defined(BOOST_FORCE_SYMMETRIC_OPERATORS)

// For compilers without NRVO the following code is optimal, but not

// symmetric!  Note that the implementation of

// BOOST_OPERATOR2_LEFT(NAME) only looks cool, but doesn't provide

// optimization opportunities to the compiler :)

#define BOOST_BINARY_OPERATOR_COMMUTATIVE( NAME, OP )                   \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct NAME##2 : B                                                      \

{                                                                       \

  friend T operator OP( T lhs, const U& rhs ) { return lhs OP##= rhs; } \

  friend T operator OP( const U& lhs, T rhs ) { return rhs OP##= lhs; } \

};                                                                      \

                                                                        \

template <class T, class B = operators_detail::empty_base<T> >          \

struct NAME##1 : B                                                      \

{                                                                       \

  friend T operator OP( T lhs, const T& rhs ) { return lhs OP##= rhs; } \

};

#define BOOST_BINARY_OPERATOR_NON_COMMUTATIVE( NAME, OP )               \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct NAME##2 : B                                                      \

{                                                                       \

  friend T operator OP( T lhs, const U& rhs ) { return lhs OP##= rhs; } \

};                                                                      \

                                                                        \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct BOOST_OPERATOR2_LEFT(NAME) : B                                   \

{                                                                       \

  friend T operator OP( const U& lhs, const T& rhs )                    \

    { return T( lhs ) OP##= rhs; }                                      \

};                                                                      \

                                                                        \

template <class T, class B = operators_detail::empty_base<T> >          \

struct NAME##1 : B                                                      \

{                                                                       \

  friend T operator OP( T lhs, const T& rhs ) { return lhs OP##= rhs; } \

};

#endif // defined(BOOST_HAS_NRVO) || defined(BOOST_FORCE_SYMMETRIC_OPERATORS)

BOOST_BINARY_OPERATOR_COMMUTATIVE( multipliable, * )

BOOST_BINARY_OPERATOR_COMMUTATIVE( addable, + )

BOOST_BINARY_OPERATOR_NON_COMMUTATIVE( subtractable, - )

BOOST_BINARY_OPERATOR_NON_COMMUTATIVE( dividable, / )

BOOST_BINARY_OPERATOR_NON_COMMUTATIVE( modable, % )

BOOST_BINARY_OPERATOR_COMMUTATIVE( xorable, ^ )

BOOST_BINARY_OPERATOR_COMMUTATIVE( andable, & )

BOOST_BINARY_OPERATOR_COMMUTATIVE( orable, | )

#undef BOOST_BINARY_OPERATOR_COMMUTATIVE

#undef BOOST_BINARY_OPERATOR_NON_COMMUTATIVE

#undef BOOST_OPERATOR2_LEFT

//  incrementable and decrementable contributed by Jeremy Siek

template <class T, class B = operators_detail::empty_base<T> >

struct incrementable : B

{

  friend T operator++(T& x, int)

  {

    incrementable_type nrv(x);

    ++x;

    return nrv;

  }

private: // The use of this typedef works around a Borland bug

  typedef T incrementable_type;

};

template <class T, class B = operators_detail::empty_base<T> >

struct decrementable : B

{

  friend T operator--(T& x, int)

  {

    decrementable_type nrv(x);

    --x;

    return nrv;

  }

private: // The use of this typedef works around a Borland bug

  typedef T decrementable_type;

};

//  Iterator operator classes (contributed by Jeremy Siek) ------------------//

template <class T, class P, class B = operators_detail::empty_base<T> >

struct dereferenceable : B

{

  P operator->() const

  {

    return ::boost::addressof(*static_cast<const T&>(*this));

  }

};

template <class T, class I, class R, class B = operators_detail::empty_base<T> >

struct indexable : B

{

  R operator[](I n) const

  {

    return *(static_cast<const T&>(*this) + n);

  }

};

//  More operator classes (contributed by Daryle Walker) --------------------//

//  (NRVO-friendly implementation contributed by Daniel Frey) ---------------//

#if defined(BOOST_HAS_NRVO) || defined(BOOST_FORCE_SYMMETRIC_OPERATORS)

#define BOOST_BINARY_OPERATOR( NAME, OP )                               \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct NAME##2 : B                                                      \

{                                                                       \

  friend T operator OP( const T& lhs, const U& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

};                                                                      \

                                                                        \

template <class T, class B = operators_detail::empty_base<T> >          \

struct NAME##1 : B                                                      \

{                                                                       \

  friend T operator OP( const T& lhs, const T& rhs )                    \

    { T nrv( lhs ); nrv OP##= rhs; return nrv; }                        \

};

#else // defined(BOOST_HAS_NRVO) || defined(BOOST_FORCE_SYMMETRIC_OPERATORS)

#define BOOST_BINARY_OPERATOR( NAME, OP )                               \

template <class T, class U, class B = operators_detail::empty_base<T> > \

struct NAME##2 : B                                                      \

{                                                                       \

  friend T operator OP( T lhs, const U& rhs ) { return lhs OP##= rhs; } \

};                                                                      \

                                                                        \

template <class T, class B = operators_detail::empty_base<T> >          \

struct NAME##1 : B                                                      \

{                                                                       \

  friend T operator OP( T lhs, const T& rhs ) { return lhs OP##= rhs; } \

};

#endif // defined(BOOST_HAS_NRVO) || defined(BOOST_FORCE_SYMMETRIC_OPERATORS)

BOOST_BINARY_OPERATOR( left_shiftable, << )

BOOST_BINARY_OPERATOR( right_shiftable, >> )

#undef BOOST_BINARY_OPERATOR

template <class T, class U, class B = operators_detail::empty_base<T> >

struct equivalent2 : B

{

  friend bool operator==(const T& x, const U& y)

  {

    return !static_cast<bool>(x < y) && !static_cast<bool>(x > y);

  }

};

template <class T, class B = operators_detail::empty_base<T> >

struct equivalent1 : B

{

  friend bool operator==(const T&x, const T&y)

  {

    return !static_cast<bool>(x < y) && !static_cast<bool>(y < x);

  }

};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct partially_ordered2 : B

{

  friend bool operator<=(const T& x, const U& y)

    { return static_cast<bool>(x < y) || static_cast<bool>(x == y); }

  friend bool operator>=(const T& x, const U& y)

    { return static_cast<bool>(x > y) || static_cast<bool>(x == y); }

  friend bool operator>(const U& x, const T& y)

    { return y < x; }

  friend bool operator<(const U& x, const T& y)

    { return y > x; }

  friend bool operator<=(const U& x, const T& y)

    { return static_cast<bool>(y > x) || static_cast<bool>(y == x); }

  friend bool operator>=(const U& x, const T& y)

    { return static_cast<bool>(y < x) || static_cast<bool>(y == x); }

};

template <class T, class B = operators_detail::empty_base<T> >

struct partially_ordered1 : B

{

  friend bool operator>(const T& x, const T& y)

    { return y < x; }

  friend bool operator<=(const T& x, const T& y)

    { return static_cast<bool>(x < y) || static_cast<bool>(x == y); }

  friend bool operator>=(const T& x, const T& y)

    { return static_cast<bool>(y < x) || static_cast<bool>(x == y); }

};

//  Combined operator classes (contributed by Daryle Walker) ----------------//

template <class T, class U, class B = operators_detail::empty_base<T> >

struct totally_ordered2

    : less_than_comparable2<T, U

    , equality_comparable2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct totally_ordered1

    : less_than_comparable1<T

    , equality_comparable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct additive2

    : addable2<T, U

    , subtractable2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct additive1

    : addable1<T

    , subtractable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct multiplicative2

    : multipliable2<T, U

    , dividable2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct multiplicative1

    : multipliable1<T

    , dividable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct integer_multiplicative2

    : multiplicative2<T, U

    , modable2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct integer_multiplicative1

    : multiplicative1<T

    , modable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct arithmetic2

    : additive2<T, U

    , multiplicative2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct arithmetic1

    : additive1<T

    , multiplicative1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct integer_arithmetic2

    : additive2<T, U

    , integer_multiplicative2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct integer_arithmetic1

    : additive1<T

    , integer_multiplicative1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct bitwise2

    : xorable2<T, U

    , andable2<T, U

    , orable2<T, U, B

      > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct bitwise1

    : xorable1<T

    , andable1<T

    , orable1<T, B

      > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct unit_steppable

    : incrementable<T

    , decrementable<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct shiftable2

    : left_shiftable2<T, U

    , right_shiftable2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct shiftable1

    : left_shiftable1<T

    , right_shiftable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct ring_operators2

    : additive2<T, U

    , subtractable2_left<T, U

    , multipliable2<T, U, B

      > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct ring_operators1

    : additive1<T

    , multipliable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct ordered_ring_operators2

    : ring_operators2<T, U

    , totally_ordered2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct ordered_ring_operators1

    : ring_operators1<T

    , totally_ordered1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct field_operators2

    : ring_operators2<T, U

    , dividable2<T, U

    , dividable2_left<T, U, B

      > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct field_operators1

    : ring_operators1<T

    , dividable1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct ordered_field_operators2

    : field_operators2<T, U

    , totally_ordered2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct ordered_field_operators1

    : field_operators1<T

    , totally_ordered1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct euclidian_ring_operators2

    : ring_operators2<T, U

    , dividable2<T, U

    , dividable2_left<T, U

    , modable2<T, U

    , modable2_left<T, U, B

      > > > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct euclidian_ring_operators1

    : ring_operators1<T

    , dividable1<T

    , modable1<T, B

      > > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct ordered_euclidian_ring_operators2

    : totally_ordered2<T, U

    , euclidian_ring_operators2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct ordered_euclidian_ring_operators1

    : totally_ordered1<T

    , euclidian_ring_operators1<T, B

      > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct euclidean_ring_operators2

    : ring_operators2<T, U

    , dividable2<T, U

    , dividable2_left<T, U

    , modable2<T, U

    , modable2_left<T, U, B

      > > > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct euclidean_ring_operators1

    : ring_operators1<T

    , dividable1<T

    , modable1<T, B

      > > > {};

template <class T, class U, class B = operators_detail::empty_base<T> >

struct ordered_euclidean_ring_operators2

    : totally_ordered2<T, U

    , euclidean_ring_operators2<T, U, B

      > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct ordered_euclidean_ring_operators1

    : totally_ordered1<T

    , euclidean_ring_operators1<T, B

      > > {};

template <class T, class P, class B = operators_detail::empty_base<T> >

struct input_iteratable

    : equality_comparable1<T

    , incrementable<T

    , dereferenceable<T, P, B

      > > > {};

template <class T, class B = operators_detail::empty_base<T> >

struct output_iteratable

    : incrementable<T, B

      > {};

template <class T, class P, class B = operators_detail::empty_base<T> >

struct forward_iteratable

    : input_iteratable<T, P, B

      > {};

template <class T, class P, class B = operators_detail::empty_base<T> >

struct bidirectional_iteratable

    : forward_iteratable<T, P

    , decrementable<T, B

      > > {};

//  To avoid repeated derivation from equality_comparable,

//  which is an indirect base class of bidirectional_iterable,

//  random_access_iteratable must not be derived from totally_ordered1

//  but from less_than_comparable1 only. (Helmut Zeisel, 02-Dec-2001)

template <class T, class P, class D, class R, class B = operators_detail::empty_base<T> >

struct random_access_iteratable

    : bidirectional_iteratable<T, P

    , less_than_comparable1<T

    , additive2<T, D

    , indexable<T, D, R, B

      > > > > {};

//

// Here's where we put it all together, defining the xxxx forms of the templates.

// We also define specializations of is_chained_base<> for

// the xxxx, xxxx1, and xxxx2 templates.

//

namespace operators_detail

{

// A type parameter is used instead of a plain bool because Borland's compiler

// didn't cope well with the more obvious non-type template parameter.

struct true_t {};

struct false_t {};

} // namespace operators_detail

// is_chained_base<> - a traits class used to distinguish whether an operator

// template argument is being used for base class chaining, or is specifying a

// 2nd argument type.

// Unspecialized version assumes that most types are not being used for base

// class chaining. We specialize for the operator templates defined in this

// library.

template<class T> struct is_chained_base {

  typedef operators_detail::false_t value;

};

// Provide a specialization of 'is_chained_base<>'

// for a 4-type-argument operator template.

# define BOOST_OPERATOR_TEMPLATE4(template_name4)           \

  template<class T, class U, class V, class W, class B>     \

  struct is_chained_base< template_name4<T, U, V, W, B> > { \

    typedef operators_detail::true_t value;                 \

  };

// Provide a specialization of 'is_chained_base<>'

// for a 3-type-argument operator template.

# define BOOST_OPERATOR_TEMPLATE3(template_name3)        \

  template<class T, class U, class V, class B>           \

  struct is_chained_base< template_name3<T, U, V, B> > { \

    typedef operators_detail::true_t value;              \

  };

// Provide a specialization of 'is_chained_base<>'

// for a 2-type-argument operator template.

# define BOOST_OPERATOR_TEMPLATE2(template_name2)     \

  template<class T, class U, class B>                 \

  struct is_chained_base< template_name2<T, U, B> > { \

    typedef operators_detail::true_t value;           \

  };

// Provide a specialization of 'is_chained_base<>'

// for a 1-type-argument operator template.

# define BOOST_OPERATOR_TEMPLATE1(template_name1)  \

  template<class T, class B>                       \

  struct is_chained_base< template_name1<T, B> > { \

    typedef operators_detail::true_t value;        \

  };

// BOOST_OPERATOR_TEMPLATE(template_name) defines template_name<> such that it

// can be used for specifying both 1-argument and 2-argument forms. Requires the

// existence of two previously defined class templates named '<template_name>1'

// and '<template_name>2' which must implement the corresponding 1- and 2-

// argument forms.

//

// The template type parameter O == is_chained_base<U>::value is used to

// distinguish whether the 2nd argument to <template_name> is being used for

// base class chaining from another boost operator template or is describing a

// 2nd operand type. O == true_t only when U is actually an another operator

// template from the library. Partial specialization is used to select an

// implementation in terms of either '<template_name>1' or '<template_name>2'.

//

# define BOOST_OPERATOR_TEMPLATE(template_name)                                       \

template <class T                                                                     \

         ,class U = T                                                                 \

         ,class B = operators_detail::empty_base<T>                                   \

         ,class O = typename is_chained_base<U>::value                                \

         >                                                                            \

struct template_name;                                                                 \

                                                                                      \

template<class T, class U, class B>                                                   \

struct template_name<T, U, B, operators_detail::false_t>                              \

  : template_name##2<T, U, B> {};                                                     \

                                                                                      \

template<class T, class U>                                                            \

struct template_name<T, U, operators_detail::empty_base<T>, operators_detail::true_t> \

  : template_name##1<T, U> {};                                                        \

                                                                                      \

template <class T, class B>                                                           \

struct template_name<T, T, B, operators_detail::false_t>                              \

  : template_name##1<T, B> {};                                                        \

                                                                                      \

template<class T, class U, class B, class O>                                          \

struct is_chained_base< template_name<T, U, B, O> > {                                 \

  typedef operators_detail::true_t value;                                             \

};                                                                                    \

                                                                                      \

BOOST_OPERATOR_TEMPLATE2(template_name##2)                                            \

BOOST_OPERATOR_TEMPLATE1(template_name##1)

BOOST_OPERATOR_TEMPLATE(less_than_comparable)

BOOST_OPERATOR_TEMPLATE(equality_comparable)

BOOST_OPERATOR_TEMPLATE(multipliable)

BOOST_OPERATOR_TEMPLATE(addable)

BOOST_OPERATOR_TEMPLATE(subtractable)

BOOST_OPERATOR_TEMPLATE2(subtractable2_left)

BOOST_OPERATOR_TEMPLATE(dividable)

BOOST_OPERATOR_TEMPLATE2(dividable2_left)

BOOST_OPERATOR_TEMPLATE(modable)

BOOST_OPERATOR_TEMPLATE2(modable2_left)

BOOST_OPERATOR_TEMPLATE(xorable)

BOOST_OPERATOR_TEMPLATE(andable)

BOOST_OPERATOR_TEMPLATE(orable)

BOOST_OPERATOR_TEMPLATE1(incrementable)

BOOST_OPERATOR_TEMPLATE1(decrementable)

BOOST_OPERATOR_TEMPLATE2(dereferenceable)

BOOST_OPERATOR_TEMPLATE3(indexable)

BOOST_OPERATOR_TEMPLATE(left_shiftable)

BOOST_OPERATOR_TEMPLATE(right_shiftable)

BOOST_OPERATOR_TEMPLATE(equivalent)

BOOST_OPERATOR_TEMPLATE(partially_ordered)

BOOST_OPERATOR_TEMPLATE(totally_ordered)

BOOST_OPERATOR_TEMPLATE(additive)

BOOST_OPERATOR_TEMPLATE(multiplicative)

BOOST_OPERATOR_TEMPLATE(integer_multiplicative)

BOOST_OPERATOR_TEMPLATE(arithmetic)

BOOST_OPERATOR_TEMPLATE(integer_arithmetic)

BOOST_OPERATOR_TEMPLATE(bitwise)

BOOST_OPERATOR_TEMPLATE1(unit_steppable)

BOOST_OPERATOR_TEMPLATE(shiftable)

BOOST_OPERATOR_TEMPLATE(ring_operators)

BOOST_OPERATOR_TEMPLATE(ordered_ring_operators)

BOOST_OPERATOR_TEMPLATE(field_operators)

BOOST_OPERATOR_TEMPLATE(ordered_field_operators)

BOOST_OPERATOR_TEMPLATE(euclidian_ring_operators)

BOOST_OPERATOR_TEMPLATE(ordered_euclidian_ring_operators)

BOOST_OPERATOR_TEMPLATE(euclidean_ring_operators)

BOOST_OPERATOR_TEMPLATE(ordered_euclidean_ring_operators)

BOOST_OPERATOR_TEMPLATE2(input_iteratable)

BOOST_OPERATOR_TEMPLATE1(output_iteratable)

BOOST_OPERATOR_TEMPLATE2(forward_iteratable)

BOOST_OPERATOR_TEMPLATE2(bidirectional_iteratable)

BOOST_OPERATOR_TEMPLATE4(random_access_iteratable)

#undef BOOST_OPERATOR_TEMPLATE

#undef BOOST_OPERATOR_TEMPLATE4

#undef BOOST_OPERATOR_TEMPLATE3

#undef BOOST_OPERATOR_TEMPLATE2

#undef BOOST_OPERATOR_TEMPLATE1

template <class T, class U>

struct operators2

    : totally_ordered2<T,U

    , integer_arithmetic2<T,U

    , bitwise2<T,U

      > > > {};

template <class T, class U = T>

struct operators : operators2<T, U> {};

template <class T> struct operators<T, T>

    : totally_ordered<T

    , integer_arithmetic<T

    , bitwise<T

    , unit_steppable<T

      > > > > {};

//  Iterator helper classes (contributed by Jeremy Siek) -------------------//

//  (Input and output iterator helpers contributed by Daryle Walker) -------//

//  (Changed to use combined operator classes by Daryle Walker) ------------//

//  (Adapted to C++17 by Daniel Frey) --------------------------------------//

template <class Category,

          class T,

          class Distance = std::ptrdiff_t,

          class Pointer = T*,

          class Reference = T&>

struct iterator_helper

{

  typedef Category iterator_category;

  typedef T value_type;

  typedef Distance difference_type;

  typedef Pointer pointer;

  typedef Reference reference;

};

template <class T,

          class V,

          class D = std::ptrdiff_t,

          class P = V const *,

          class R = V const &>

struct input_iterator_helper

  : input_iteratable<T, P

  , iterator_helper<std::input_iterator_tag, V, D, P, R

    > > {};

template<class T>

struct output_iterator_helper

  : output_iteratable<T

  , iterator_helper<std::output_iterator_tag, void, void, void, void

  > >

{

  T& operator*()  { return static_cast<T&>(*this); }

  T& operator++() { return static_cast<T&>(*this); }

};

template <class T,

          class V,

          class D = std::ptrdiff_t,

          class P = V*,

          class R = V&>

struct forward_iterator_helper

  : forward_iteratable<T, P

  , iterator_helper<std::forward_iterator_tag, V, D, P, R

    > > {};

template <class T,

          class V,

          class D = std::ptrdiff_t,

          class P = V*,

          class R = V&>

struct bidirectional_iterator_helper

  : bidirectional_iteratable<T, P

  , iterator_helper<std::bidirectional_iterator_tag, V, D, P, R

    > > {};

template <class T,

          class V,

          class D = std::ptrdiff_t,

          class P = V*,

          class R = V&>

struct random_access_iterator_helper

  : random_access_iteratable<T, P, D, R

  , iterator_helper<std::random_access_iterator_tag, V, D, P, R

    > >

{

  friend D requires_difference_operator(const T& x, const T& y) {

    return x - y;

  }

}; // random_access_iterator_helper

} // namespace operators_impl

using namespace operators_impl;

} // namespace boost

#if defined(__sgi) && !defined(__GNUC__)

#pragma reset woff 1234

#endif

#endif // BOOST_NO_OPERATORS_IN_NAMESPACE

#endif // BOOST_OPERATORS_HPP