boost/operators.hpp
// 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
// Define BOOST_OPERATORS_CONSTEXPR to be like BOOST_CONSTEXPR but empty under MSVC < v19.22
#if BOOST_WORKAROUND(BOOST_MSVC, < 1922)
#define BOOST_OPERATORS_CONSTEXPR
#elif defined __sun
#define BOOST_OPERATORS_CONSTEXPR
#else
#define BOOST_OPERATORS_CONSTEXPR BOOST_CONSTEXPR
#endif
// 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 BOOST_OPERATORS_CONSTEXPR bool operator<=(const T& x, const U& y) { return !static_cast<bool>(x > y); }
friend BOOST_OPERATORS_CONSTEXPR bool operator>=(const T& x, const U& y) { return !static_cast<bool>(x < y); }
friend BOOST_OPERATORS_CONSTEXPR bool operator>(const U& x, const T& y) { return y < x; }
friend BOOST_OPERATORS_CONSTEXPR bool operator<(const U& x, const T& y) { return y > x; }
friend BOOST_OPERATORS_CONSTEXPR bool operator<=(const U& x, const T& y) { return !static_cast<bool>(y < x); }
friend BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR bool operator>(const T& x, const T& y) { return y < x; }
friend BOOST_OPERATORS_CONSTEXPR bool operator<=(const T& x, const T& y) { return !static_cast<bool>(y < x); }
friend BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR bool operator==(const U& y, const T& x) { return x == y; }
friend BOOST_OPERATORS_CONSTEXPR bool operator!=(const U& y, const T& x) { return !static_cast<bool>(x == y); }
friend BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR bool operator<=(const T& x, const U& y)
{ return static_cast<bool>(x < y) || static_cast<bool>(x == y); }
friend BOOST_OPERATORS_CONSTEXPR bool operator>=(const T& x, const U& y)
{ return static_cast<bool>(x > y) || static_cast<bool>(x == y); }
friend BOOST_OPERATORS_CONSTEXPR bool operator>(const U& x, const T& y)
{ return y < x; }
friend BOOST_OPERATORS_CONSTEXPR bool operator<(const U& x, const T& y)
{ return y > x; }
friend BOOST_OPERATORS_CONSTEXPR bool operator<=(const U& x, const T& y)
{ return static_cast<bool>(y > x) || static_cast<bool>(y == x); }
friend BOOST_OPERATORS_CONSTEXPR 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 BOOST_OPERATORS_CONSTEXPR bool operator>(const T& x, const T& y)
{ return y < x; }
friend BOOST_OPERATORS_CONSTEXPR bool operator<=(const T& x, const T& y)
{ return static_cast<bool>(x < y) || static_cast<bool>(x == y); }
friend BOOST_OPERATORS_CONSTEXPR 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