boost/operators.hpp
// Boost operators.hpp header file ----------------------------------------// // (C) Copyright David Abrahams, Jeremy Siek, Daryle Walker 1999-2001. // 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) // See http://www.boost.org/libs/utility/operators.htm for documentation. // Revision History // 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 '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 #include <boost/config.hpp> #include <boost/iterator.hpp> #include <boost/detail/workaround.hpp> #if defined(__sgi) && !defined(__GNUC__) # pragma set woff 1234 #endif #if defined(BOOST_MSVC) # pragma warning( disable : 4284 ) // complaint about return type of #endif // operator-> not begin a UDT namespace boost { namespace detail { template <typename T> class empty_base { // Helmut Zeisel, empty base class optimization bug with GCC 3.0.0 #if defined(__GNUC__) && __GNUC__==3 && __GNUC_MINOR__==0 && __GNU_PATCHLEVEL__==0 bool dummy; #endif }; } // namespace detail } // namespace boost // 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. Some compilers get confused // when inline friend functions are overloaded in namespaces other than the // global namespace. When BOOST_NO_OPERATORS_IN_NAMESPACE is defined, all of // these templates must go in the global namespace. #ifndef BOOST_NO_OPERATORS_IN_NAMESPACE namespace boost { #endif // 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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::detail::empty_base<T> > struct dereferenceable : B { P operator->() const { return &*static_cast<const T&>(*this); } }; template <class T, class I, class R, class B = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::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 = ::boost::detail::empty_base<T> > struct totally_ordered2 : less_than_comparable2<T, U , equality_comparable2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct totally_ordered1 : less_than_comparable1<T , equality_comparable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct additive2 : addable2<T, U , subtractable2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct additive1 : addable1<T , subtractable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct multiplicative2 : multipliable2<T, U , dividable2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct multiplicative1 : multipliable1<T , dividable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct integer_multiplicative2 : multiplicative2<T, U , modable2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct integer_multiplicative1 : multiplicative1<T , modable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct arithmetic2 : additive2<T, U , multiplicative2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct arithmetic1 : additive1<T , multiplicative1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct integer_arithmetic2 : additive2<T, U , integer_multiplicative2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct integer_arithmetic1 : additive1<T , integer_multiplicative1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct bitwise2 : xorable2<T, U , andable2<T, U , orable2<T, U, B > > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct bitwise1 : xorable1<T , andable1<T , orable1<T, B > > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct unit_steppable : incrementable<T , decrementable<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct shiftable2 : left_shiftable2<T, U , right_shiftable2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct shiftable1 : left_shiftable1<T , right_shiftable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct ring_operators2 : additive2<T, U , subtractable2_left<T, U , multipliable2<T, U, B > > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct ring_operators1 : additive1<T , multipliable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct ordered_ring_operators2 : ring_operators2<T, U , totally_ordered2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct ordered_ring_operators1 : ring_operators1<T , totally_ordered1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct field_operators2 : ring_operators2<T, U , dividable2<T, U , dividable2_left<T, U, B > > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct field_operators1 : ring_operators1<T , dividable1<T, B > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct ordered_field_operators2 : field_operators2<T, U , totally_ordered2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct ordered_field_operators1 : field_operators1<T , totally_ordered1<T, B > > {}; template <class T, class U, class B = ::boost::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 = ::boost::detail::empty_base<T> > struct euclidian_ring_operators1 : ring_operators1<T , dividable1<T , modable1<T, B > > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct ordered_euclidian_ring_operators2 : totally_ordered2<T, U , euclidian_ring_operators2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct ordered_euclidian_ring_operators1 : totally_ordered1<T , euclidian_ring_operators1<T, B > > {}; template <class T, class U, class B = ::boost::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 = ::boost::detail::empty_base<T> > struct euclidean_ring_operators1 : ring_operators1<T , dividable1<T , modable1<T, B > > > {}; template <class T, class U, class B = ::boost::detail::empty_base<T> > struct ordered_euclidean_ring_operators2 : totally_ordered2<T, U , euclidean_ring_operators2<T, U, B > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct ordered_euclidean_ring_operators1 : totally_ordered1<T , euclidean_ring_operators1<T, B > > {}; template <class T, class P, class B = ::boost::detail::empty_base<T> > struct input_iteratable : equality_comparable1<T , incrementable<T , dereferenceable<T, P, B > > > {}; template <class T, class B = ::boost::detail::empty_base<T> > struct output_iteratable : incrementable<T, B > {}; template <class T, class P, class B = ::boost::detail::empty_base<T> > struct forward_iteratable : input_iteratable<T, P, B > {}; template <class T, class P, class B = ::boost::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 = ::boost::detail::empty_base<T> > struct random_access_iteratable : bidirectional_iteratable<T, P , less_than_comparable1<T , additive2<T, D , indexable<T, D, R, B > > > > {}; #ifndef BOOST_NO_OPERATORS_IN_NAMESPACE } // namespace boost #endif // BOOST_NO_OPERATORS_IN_NAMESPACE // BOOST_IMPORT_TEMPLATE1 .. BOOST_IMPORT_TEMPLATE4 - // // When BOOST_NO_OPERATORS_IN_NAMESPACE is defined we need a way to import an // operator template into the boost namespace. BOOST_IMPORT_TEMPLATE1 is used // for one-argument forms of operator templates; BOOST_IMPORT_TEMPLATE2 for // two-argument forms. Note that these macros expect to be invoked from within // boost. #ifndef BOOST_NO_OPERATORS_IN_NAMESPACE // The template is already in boost so we have nothing to do. # define BOOST_IMPORT_TEMPLATE4(template_name) # define BOOST_IMPORT_TEMPLATE3(template_name) # define BOOST_IMPORT_TEMPLATE2(template_name) # define BOOST_IMPORT_TEMPLATE1(template_name) #else // BOOST_NO_OPERATORS_IN_NAMESPACE # ifndef BOOST_NO_USING_TEMPLATE // Bring the names in with a using-declaration // to avoid stressing the compiler. # define BOOST_IMPORT_TEMPLATE4(template_name) using ::template_name; # define BOOST_IMPORT_TEMPLATE3(template_name) using ::template_name; # define BOOST_IMPORT_TEMPLATE2(template_name) using ::template_name; # define BOOST_IMPORT_TEMPLATE1(template_name) using ::template_name; # else // Otherwise, because a Borland C++ 5.5 bug prevents a using declaration // from working, we are forced to use inheritance for that compiler. # define BOOST_IMPORT_TEMPLATE4(template_name) \ template <class T, class U, class V, class W, class B = ::boost::detail::empty_base<T> > \ struct template_name : ::template_name<T, U, V, W, B> {}; # define BOOST_IMPORT_TEMPLATE3(template_name) \ template <class T, class U, class V, class B = ::boost::detail::empty_base<T> > \ struct template_name : ::template_name<T, U, V, B> {}; # define BOOST_IMPORT_TEMPLATE2(template_name) \ template <class T, class U, class B = ::boost::detail::empty_base<T> > \ struct template_name : ::template_name<T, U, B> {}; # define BOOST_IMPORT_TEMPLATE1(template_name) \ template <class T, class B = ::boost::detail::empty_base<T> > \ struct template_name : ::template_name<T, B> {}; # endif // BOOST_NO_USING_TEMPLATE #endif // BOOST_NO_OPERATORS_IN_NAMESPACE // // Here's where we put it all together, defining the xxxx forms of the templates // in namespace boost. We also define specializations of is_chained_base<> for // the xxxx, xxxx1, and xxxx2 templates, importing them into boost:: as // necessary. // #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION // 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. namespace boost { // 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. namespace detail { struct true_t {}; struct false_t {}; } // namespace detail // 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 ::boost::detail::false_t value; }; } // namespace boost // Import a 4-type-argument operator template into boost (if necessary) and // provide a specialization of 'is_chained_base<>' for it. # define BOOST_OPERATOR_TEMPLATE4(template_name4) \ BOOST_IMPORT_TEMPLATE4(template_name4) \ template<class T, class U, class V, class W, class B> \ struct is_chained_base< ::boost::template_name4<T, U, V, W, B> > { \ typedef ::boost::detail::true_t value; \ }; // Import a 3-type-argument operator template into boost (if necessary) and // provide a specialization of 'is_chained_base<>' for it. # define BOOST_OPERATOR_TEMPLATE3(template_name3) \ BOOST_IMPORT_TEMPLATE3(template_name3) \ template<class T, class U, class V, class B> \ struct is_chained_base< ::boost::template_name3<T, U, V, B> > { \ typedef ::boost::detail::true_t value; \ }; // Import a 2-type-argument operator template into boost (if necessary) and // provide a specialization of 'is_chained_base<>' for it. # define BOOST_OPERATOR_TEMPLATE2(template_name2) \ BOOST_IMPORT_TEMPLATE2(template_name2) \ template<class T, class U, class B> \ struct is_chained_base< ::boost::template_name2<T, U, B> > { \ typedef ::boost::detail::true_t value; \ }; // Import a 1-type-argument operator template into boost (if necessary) and // provide a specialization of 'is_chained_base<>' for it. # define BOOST_OPERATOR_TEMPLATE1(template_name1) \ BOOST_IMPORT_TEMPLATE1(template_name1) \ template<class T, class B> \ struct is_chained_base< ::boost::template_name1<T, B> > { \ typedef ::boost::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 = ::boost::detail::empty_base<T> \ ,class O = typename is_chained_base<U>::value \ > \ struct template_name : template_name##2<T, U, B> {}; \ \ template<class T, class U, class B> \ struct template_name<T, U, B, ::boost::detail::true_t> \ : template_name##1<T, U> {}; \ \ template <class T, class B> \ struct template_name<T, T, B, ::boost::detail::false_t> \ : template_name##1<T, B> {}; \ \ template<class T, class U, class B, class O> \ struct is_chained_base< ::boost::template_name<T, U, B, O> > { \ typedef ::boost::detail::true_t value; \ }; \ \ BOOST_OPERATOR_TEMPLATE2(template_name##2) \ BOOST_OPERATOR_TEMPLATE1(template_name##1) #else // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION # define BOOST_OPERATOR_TEMPLATE4(template_name4) \ BOOST_IMPORT_TEMPLATE4(template_name4) # define BOOST_OPERATOR_TEMPLATE3(template_name3) \ BOOST_IMPORT_TEMPLATE3(template_name3) # define BOOST_OPERATOR_TEMPLATE2(template_name2) \ BOOST_IMPORT_TEMPLATE2(template_name2) # define BOOST_OPERATOR_TEMPLATE1(template_name1) \ BOOST_IMPORT_TEMPLATE1(template_name1) // In this case we can only assume that template_name<> is equivalent to the // more commonly needed template_name1<> form. # define BOOST_OPERATOR_TEMPLATE(template_name) \ template <class T, class B = ::boost::detail::empty_base<T> > \ struct template_name : template_name##1<T, B> {}; #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION namespace boost { 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 #undef BOOST_IMPORT_TEMPLATE1 #undef BOOST_IMPORT_TEMPLATE2 #undef BOOST_IMPORT_TEMPLATE3 #undef BOOST_IMPORT_TEMPLATE4 // The following 'operators' classes can only be used portably if the derived class // declares ALL of the required member operators. template <class T, class U> struct operators2 : totally_ordered2<T,U , integer_arithmetic2<T,U , bitwise2<T,U > > > {}; #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION template <class T, class U = T> struct operators : operators2<T, U> {}; template <class T> struct operators<T, T> #else template <class T> struct operators #endif : 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) ------------// 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 , boost::iterator<std::input_iterator_tag, V, D, P, R > > {}; template<class T> struct output_iterator_helper : output_iteratable<T , boost::iterator<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 , boost::iterator<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 , boost::iterator<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 , boost::iterator<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 boost #if defined(__sgi) && !defined(__GNUC__) #pragma reset woff 1234 #endif #endif // BOOST_OPERATORS_HPP