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diff --git a/contrib/libstdc++/include/ext/functional b/contrib/libstdc++/include/ext/functional new file mode 100644 index 0000000..c482aa1 --- /dev/null +++ b/contrib/libstdc++/include/ext/functional @@ -0,0 +1,395 @@ +// Functional extensions -*- C++ -*- + +// Copyright (C) 2002 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 2, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING. If not, write to the Free +// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, +// USA. + +// As a special exception, you may use this file as part of a free software +// library without restriction. Specifically, if other files instantiate +// templates or use macros or inline functions from this file, or you compile +// this file and link it with other files to produce an executable, this +// file does not by itself cause the resulting executable to be covered by +// the GNU General Public License. This exception does not however +// invalidate any other reasons why the executable file might be covered by +// the GNU General Public License. + +/* + * + * Copyright (c) 1994 + * Hewlett-Packard Company + * + * Permission to use, copy, modify, distribute and sell this software + * and its documentation for any purpose is hereby granted without fee, + * provided that the above copyright notice appear in all copies and + * that both that copyright notice and this permission notice appear + * in supporting documentation. Hewlett-Packard Company makes no + * representations about the suitability of this software for any + * purpose. It is provided "as is" without express or implied warranty. + * + * + * Copyright (c) 1996 + * Silicon Graphics Computer Systems, Inc. + * + * Permission to use, copy, modify, distribute and sell this software + * and its documentation for any purpose is hereby granted without fee, + * provided that the above copyright notice appear in all copies and + * that both that copyright notice and this permission notice appear + * in supporting documentation. Silicon Graphics makes no + * representations about the suitability of this software for any + * purpose. It is provided "as is" without express or implied warranty. + */ + +/** @file ext/functional + * This file is a GNU extension to the Standard C++ Library (possibly + * containing extensions from the HP/SGI STL subset). You should only + * include this header if you are using GCC 3 or later. + */ + +#ifndef _EXT_FUNCTIONAL +#define _EXT_FUNCTIONAL + +#pragma GCC system_header +#include <functional> + +namespace __gnu_cxx +{ +using std::unary_function; +using std::binary_function; +using std::mem_fun1_t; +using std::const_mem_fun1_t; +using std::mem_fun1_ref_t; +using std::const_mem_fun1_ref_t; + +/** The @c identity_element functions are not part of the C++ standard; SGI + * provided them as an extension. Its argument is an operation, and its + * return value is the identity element for that operation. It is overloaded + * for addition and multiplication, and you can overload it for your own + * nefarious operations. + * + * @addtogroup SGIextensions + * @{ +*/ +/// An \link SGIextensions SGI extension \endlink. +template <class _Tp> inline _Tp identity_element(std::plus<_Tp>) { + return _Tp(0); +} +/// An \link SGIextensions SGI extension \endlink. +template <class _Tp> inline _Tp identity_element(std::multiplies<_Tp>) { + return _Tp(1); +} +/** @} */ + +/** As an extension to the binders, SGI provided composition functors and + * wrapper functions to aid in their creation. The @c unary_compose + * functor is constructed from two functions/functors, @c f and @c g. + * Calling @c operator() with a single argument @c x returns @c f(g(x)). + * The function @c compose1 takes the two functions and constructs a + * @c unary_compose variable for you. + * + * @c binary_compose is constructed from three functors, @c f, @c g1, + * and @c g2. Its @c operator() returns @c f(g1(x),g2(x)). The function + * @compose2 takes f, g1, and g2, and constructs the @c binary_compose + * instance for you. For example, if @c f returns an int, then + * \code + * int answer = (compose2(f,g1,g2))(x); + * \endcode + * is equivalent to + * \code + * int temp1 = g1(x); + * int temp2 = g2(x); + * int answer = f(temp1,temp2); + * \endcode + * But the first form is more compact, and can be passed around as a + * functor to other algorithms. + * + * @addtogroup SGIextensions + * @{ +*/ +/// An \link SGIextensions SGI extension \endlink. +template <class _Operation1, class _Operation2> +class unary_compose + : public unary_function<typename _Operation2::argument_type, + typename _Operation1::result_type> +{ +protected: + _Operation1 _M_fn1; + _Operation2 _M_fn2; +public: + unary_compose(const _Operation1& __x, const _Operation2& __y) + : _M_fn1(__x), _M_fn2(__y) {} + typename _Operation1::result_type + operator()(const typename _Operation2::argument_type& __x) const { + return _M_fn1(_M_fn2(__x)); + } +}; + +/// An \link SGIextensions SGI extension \endlink. +template <class _Operation1, class _Operation2> +inline unary_compose<_Operation1,_Operation2> +compose1(const _Operation1& __fn1, const _Operation2& __fn2) +{ + return unary_compose<_Operation1,_Operation2>(__fn1, __fn2); +} + +/// An \link SGIextensions SGI extension \endlink. +template <class _Operation1, class _Operation2, class _Operation3> +class binary_compose + : public unary_function<typename _Operation2::argument_type, + typename _Operation1::result_type> { +protected: + _Operation1 _M_fn1; + _Operation2 _M_fn2; + _Operation3 _M_fn3; +public: + binary_compose(const _Operation1& __x, const _Operation2& __y, + const _Operation3& __z) + : _M_fn1(__x), _M_fn2(__y), _M_fn3(__z) { } + typename _Operation1::result_type + operator()(const typename _Operation2::argument_type& __x) const { + return _M_fn1(_M_fn2(__x), _M_fn3(__x)); + } +}; + +/// An \link SGIextensions SGI extension \endlink. +template <class _Operation1, class _Operation2, class _Operation3> +inline binary_compose<_Operation1, _Operation2, _Operation3> +compose2(const _Operation1& __fn1, const _Operation2& __fn2, + const _Operation3& __fn3) +{ + return binary_compose<_Operation1,_Operation2,_Operation3> + (__fn1, __fn2, __fn3); +} +/** @} */ + +/** As an extension, SGI provided a functor called @c identity. When a + * functor is required but no operations are desired, this can be used as a + * pass-through. Its @c operator() returns its argument unchanged. + * + * @addtogroup SGIextensions +*/ +template <class _Tp> struct identity : public std::_Identity<_Tp> {}; + +/** @c select1st and @c select2nd are extensions provided by SGI. Their + * @c operator()s + * take a @c std::pair as an argument, and return either the first member + * or the second member, respectively. They can be used (especially with + * the composition functors) to "strip" data from a sequence before + * performing the remainder of an algorithm. + * + * @addtogroup SGIextensions + * @{ +*/ +/// An \link SGIextensions SGI extension \endlink. +template <class _Pair> struct select1st : public std::_Select1st<_Pair> {}; +/// An \link SGIextensions SGI extension \endlink. +template <class _Pair> struct select2nd : public std::_Select2nd<_Pair> {}; +/** @} */ + +// extension documented next +template <class _Arg1, class _Arg2> +struct _Project1st : public binary_function<_Arg1, _Arg2, _Arg1> { + _Arg1 operator()(const _Arg1& __x, const _Arg2&) const { return __x; } +}; + +template <class _Arg1, class _Arg2> +struct _Project2nd : public binary_function<_Arg1, _Arg2, _Arg2> { + _Arg2 operator()(const _Arg1&, const _Arg2& __y) const { return __y; } +}; + +/** The @c operator() of the @c project1st functor takes two arbitrary + * arguments and returns the first one, while @c project2nd returns the + * second one. They are extensions provided by SGI. + * + * @addtogroup SGIextensions + * @{ +*/ + +/// An \link SGIextensions SGI extension \endlink. +template <class _Arg1, class _Arg2> +struct project1st : public _Project1st<_Arg1, _Arg2> {}; + +/// An \link SGIextensions SGI extension \endlink. +template <class _Arg1, class _Arg2> +struct project2nd : public _Project2nd<_Arg1, _Arg2> {}; +/** @} */ + +// extension documented next +template <class _Result> +struct _Constant_void_fun { + typedef _Result result_type; + result_type _M_val; + + _Constant_void_fun(const result_type& __v) : _M_val(__v) {} + const result_type& operator()() const { return _M_val; } +}; + +template <class _Result, class _Argument> +struct _Constant_unary_fun { + typedef _Argument argument_type; + typedef _Result result_type; + result_type _M_val; + + _Constant_unary_fun(const result_type& __v) : _M_val(__v) {} + const result_type& operator()(const _Argument&) const { return _M_val; } +}; + +template <class _Result, class _Arg1, class _Arg2> +struct _Constant_binary_fun { + typedef _Arg1 first_argument_type; + typedef _Arg2 second_argument_type; + typedef _Result result_type; + _Result _M_val; + + _Constant_binary_fun(const _Result& __v) : _M_val(__v) {} + const result_type& operator()(const _Arg1&, const _Arg2&) const { + return _M_val; + } +}; + +/** These three functors are each constructed from a single arbitrary + * variable/value. Later, their @c operator()s completely ignore any + * arguments passed, and return the stored value. + * - @c constant_void_fun's @c operator() takes no arguments + * - @c constant_unary_fun's @c operator() takes one argument (ignored) + * - @c constant_binary_fun's @c operator() takes two arguments (ignored) + * + * The helper creator functions @c constant0, @c constant1, and + * @c constant2 each take a "result" argument and construct variables of + * the appropriate functor type. + * + * @addtogroup SGIextensions + * @{ +*/ +/// An \link SGIextensions SGI extension \endlink. +template <class _Result> +struct constant_void_fun : public _Constant_void_fun<_Result> { + constant_void_fun(const _Result& __v) : _Constant_void_fun<_Result>(__v) {} +}; + +/// An \link SGIextensions SGI extension \endlink. +template <class _Result, + class _Argument = _Result> +struct constant_unary_fun : public _Constant_unary_fun<_Result, _Argument> +{ + constant_unary_fun(const _Result& __v) + : _Constant_unary_fun<_Result, _Argument>(__v) {} +}; + +/// An \link SGIextensions SGI extension \endlink. +template <class _Result, + class _Arg1 = _Result, + class _Arg2 = _Arg1> +struct constant_binary_fun + : public _Constant_binary_fun<_Result, _Arg1, _Arg2> +{ + constant_binary_fun(const _Result& __v) + : _Constant_binary_fun<_Result, _Arg1, _Arg2>(__v) {} +}; + +/// An \link SGIextensions SGI extension \endlink. +template <class _Result> +inline constant_void_fun<_Result> constant0(const _Result& __val) +{ + return constant_void_fun<_Result>(__val); +} + +/// An \link SGIextensions SGI extension \endlink. +template <class _Result> +inline constant_unary_fun<_Result,_Result> constant1(const _Result& __val) +{ + return constant_unary_fun<_Result,_Result>(__val); +} + +/// An \link SGIextensions SGI extension \endlink. +template <class _Result> +inline constant_binary_fun<_Result,_Result,_Result> +constant2(const _Result& __val) +{ + return constant_binary_fun<_Result,_Result,_Result>(__val); +} +/** @} */ + +/** The @c subtractive_rng class is documented on + * <a href="http://www.sgi.com/tech/stl/">SGI's site</a>. + * Note that this code assumes that @c int is 32 bits. + * + * @ingroup SGIextensions +*/ +class subtractive_rng : public unary_function<unsigned int, unsigned int> { +private: + unsigned int _M_table[55]; + size_t _M_index1; + size_t _M_index2; +public: + /// Returns a number less than the argument. + unsigned int operator()(unsigned int __limit) { + _M_index1 = (_M_index1 + 1) % 55; + _M_index2 = (_M_index2 + 1) % 55; + _M_table[_M_index1] = _M_table[_M_index1] - _M_table[_M_index2]; + return _M_table[_M_index1] % __limit; + } + + void _M_initialize(unsigned int __seed) + { + unsigned int __k = 1; + _M_table[54] = __seed; + size_t __i; + for (__i = 0; __i < 54; __i++) { + size_t __ii = (21 * (__i + 1) % 55) - 1; + _M_table[__ii] = __k; + __k = __seed - __k; + __seed = _M_table[__ii]; + } + for (int __loop = 0; __loop < 4; __loop++) { + for (__i = 0; __i < 55; __i++) + _M_table[__i] = _M_table[__i] - _M_table[(1 + __i + 30) % 55]; + } + _M_index1 = 0; + _M_index2 = 31; + } + + /// Ctor allowing you to initialize the seed. + subtractive_rng(unsigned int __seed) { _M_initialize(__seed); } + /// Default ctor; initializes its state with some number you don't see. + subtractive_rng() { _M_initialize(161803398u); } +}; + +// Mem_fun adaptor helper functions mem_fun1 and mem_fun1_ref, +// provided for backward compatibility, they are no longer part of +// the C++ standard. + +template <class _Ret, class _Tp, class _Arg> +inline mem_fun1_t<_Ret,_Tp,_Arg> mem_fun1(_Ret (_Tp::*__f)(_Arg)) + { return mem_fun1_t<_Ret,_Tp,_Arg>(__f); } + +template <class _Ret, class _Tp, class _Arg> +inline const_mem_fun1_t<_Ret,_Tp,_Arg> mem_fun1(_Ret (_Tp::*__f)(_Arg) const) + { return const_mem_fun1_t<_Ret,_Tp,_Arg>(__f); } + +template <class _Ret, class _Tp, class _Arg> +inline mem_fun1_ref_t<_Ret,_Tp,_Arg> mem_fun1_ref(_Ret (_Tp::*__f)(_Arg)) + { return mem_fun1_ref_t<_Ret,_Tp,_Arg>(__f); } + +template <class _Ret, class _Tp, class _Arg> +inline const_mem_fun1_ref_t<_Ret,_Tp,_Arg> +mem_fun1_ref(_Ret (_Tp::*__f)(_Arg) const) + { return const_mem_fun1_ref_t<_Ret,_Tp,_Arg>(__f); } + +} // namespace __gnu_cxx + +#endif /* _EXT_FUNCTIONAL */ + |
