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Diffstat (limited to 'contrib/libstdc++/include/bits/stl_algobase.h')
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diff --git a/contrib/libstdc++/include/bits/stl_algobase.h b/contrib/libstdc++/include/bits/stl_algobase.h new file mode 100644 index 0000000..6e488ea --- /dev/null +++ b/contrib/libstdc++/include/bits/stl_algobase.h @@ -0,0 +1,820 @@ +// Bits and pieces used in algorithms -*- C++ -*- + +// Copyright (C) 2001, 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) 1996-1998 + * 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 stl_algobase.h + * This is an internal header file, included by other library headers. + * You should not attempt to use it directly. + */ + +#ifndef __GLIBCPP_INTERNAL_ALGOBASE_H +#define __GLIBCPP_INTERNAL_ALGOBASE_H + +#include <bits/c++config.h> +#include <cstring> +#include <climits> +#include <cstdlib> +#include <cstddef> +#include <new> +#include <iosfwd> +#include <bits/stl_pair.h> +#include <bits/type_traits.h> +#include <bits/stl_iterator_base_types.h> +#include <bits/stl_iterator_base_funcs.h> +#include <bits/stl_iterator.h> +#include <bits/concept_check.h> + +namespace std +{ + // swap and iter_swap + + /** + * @brief Swaps the contents of two iterators. + * @param a An iterator. + * @param b Another iterator. + * @return Nothing. + * + * This function swaps the values pointed to by two iterators, not the + * iterators themselves. + */ + template<typename _ForwardIter1, typename _ForwardIter2> + inline void + iter_swap(_ForwardIter1 __a, _ForwardIter2 __b) + { + typedef typename iterator_traits<_ForwardIter1>::value_type _ValueType1; + typedef typename iterator_traits<_ForwardIter2>::value_type _ValueType2; + + // concept requirements + __glibcpp_function_requires(_Mutable_ForwardIteratorConcept<_ForwardIter1>) + __glibcpp_function_requires(_Mutable_ForwardIteratorConcept<_ForwardIter2>) + __glibcpp_function_requires(_ConvertibleConcept<_ValueType1, _ValueType2>) + __glibcpp_function_requires(_ConvertibleConcept<_ValueType2, _ValueType1>) + + _ValueType1 __tmp = *__a; + *__a = *__b; + *__b = __tmp; + } + + /** + * @brief Swaps two values. + * @param a A thing of arbitrary type. + * @param b Another thing of arbitrary type. + * @return Nothing. + * + * This is the simple classic generic implementation. It will work on + * any type which has a copy constructor and an assignment operator. + */ + template<typename _Tp> + inline void + swap(_Tp& __a, _Tp& __b) + { + // concept requirements + __glibcpp_function_requires(_SGIAssignableConcept<_Tp>) + + _Tp __tmp = __a; + __a = __b; + __b = __tmp; + } + + //-------------------------------------------------- + // min and max + + #undef min + #undef max + + /** + * @brief This does what you think it does. + * @param a A thing of arbitrary type. + * @param b Another thing of arbitrary type. + * @return The lesser of the parameters. + * + * This is the simple classic generic implementation. It will work on + * temporary expressions, since they are only evaluated once, unlike a + * preprocessor macro. + */ + template<typename _Tp> + inline const _Tp& + min(const _Tp& __a, const _Tp& __b) + { + // concept requirements + __glibcpp_function_requires(_LessThanComparableConcept<_Tp>) + //return __b < __a ? __b : __a; + if (__b < __a) return __b; return __a; + } + + /** + * @brief This does what you think it does. + * @param a A thing of arbitrary type. + * @param b Another thing of arbitrary type. + * @return The greater of the parameters. + * + * This is the simple classic generic implementation. It will work on + * temporary expressions, since they are only evaluated once, unlike a + * preprocessor macro. + */ + template<typename _Tp> + inline const _Tp& + max(const _Tp& __a, const _Tp& __b) + { + // concept requirements + __glibcpp_function_requires(_LessThanComparableConcept<_Tp>) + //return __a < __b ? __b : __a; + if (__a < __b) return __b; return __a; + } + + /** + * @brief This does what you think it does. + * @param a A thing of arbitrary type. + * @param b Another thing of arbitrary type. + * @param comp A @link s20_3_3_comparisons comparison functor@endlink. + * @return The lesser of the parameters. + * + * This will work on temporary expressions, since they are only evaluated + * once, unlike a preprocessor macro. + */ + template<typename _Tp, typename _Compare> + inline const _Tp& + min(const _Tp& __a, const _Tp& __b, _Compare __comp) + { + //return __comp(__b, __a) ? __b : __a; + if (__comp(__b, __a)) return __b; return __a; + } + + /** + * @brief This does what you think it does. + * @param a A thing of arbitrary type. + * @param b Another thing of arbitrary type. + * @param comp A @link s20_3_3_comparisons comparison functor@endlink. + * @return The greater of the parameters. + * + * This will work on temporary expressions, since they are only evaluated + * once, unlike a preprocessor macro. + */ + template<typename _Tp, typename _Compare> + inline const _Tp& + max(const _Tp& __a, const _Tp& __b, _Compare __comp) + { + //return __comp(__a, __b) ? __b : __a; + if (__comp(__a, __b)) return __b; return __a; + } + + //-------------------------------------------------- + // copy + + // All of these auxiliary functions serve two purposes. (1) Replace + // calls to copy with memmove whenever possible. (Memmove, not memcpy, + // because the input and output ranges are permitted to overlap.) + // (2) If we're using random access iterators, then write the loop as + // a for loop with an explicit count. + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy(_InputIter __first, _InputIter __last, + _OutputIter __result, + input_iterator_tag) + { + for ( ; __first != __last; ++__result, ++__first) + *__result = *__first; + return __result; + } + + template<typename _RandomAccessIter, typename _OutputIter> + inline _OutputIter + __copy(_RandomAccessIter __first, _RandomAccessIter __last, + _OutputIter __result, + random_access_iterator_tag) + { + typedef typename iterator_traits<_RandomAccessIter>::difference_type + _Distance; + for (_Distance __n = __last - __first; __n > 0; --__n) { + *__result = *__first; + ++__first; + ++__result; + } + return __result; + } + + template<typename _Tp> + inline _Tp* + __copy_trivial(const _Tp* __first, const _Tp* __last, _Tp* __result) + { + memmove(__result, __first, sizeof(_Tp) * (__last - __first)); + return __result + (__last - __first); + } + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy_aux2(_InputIter __first, _InputIter __last, + _OutputIter __result, __false_type) + { return __copy(__first, __last, __result, __iterator_category(__first)); } + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy_aux2(_InputIter __first, _InputIter __last, + _OutputIter __result, __true_type) + { return __copy(__first, __last, __result, __iterator_category(__first)); } + + template<typename _Tp> + inline _Tp* + __copy_aux2(_Tp* __first, _Tp* __last, + _Tp* __result, __true_type) + { return __copy_trivial(__first, __last, __result); } + + template<typename _Tp> + inline _Tp* + __copy_aux2(const _Tp* __first, const _Tp* __last, + _Tp* __result, __true_type) + { return __copy_trivial(__first, __last, __result); } + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy_ni2(_InputIter __first, _InputIter __last, + _OutputIter __result, __true_type) + { + typedef typename iterator_traits<_InputIter>::value_type + _ValueType; + typedef typename __type_traits<_ValueType>::has_trivial_assignment_operator + _Trivial; + return _OutputIter(__copy_aux2(__first, __last, + __result.base(), + _Trivial())); + } + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy_ni2(_InputIter __first, _InputIter __last, + _OutputIter __result, __false_type) + { + typedef typename iterator_traits<_InputIter>::value_type + _ValueType; + typedef typename __type_traits<_ValueType>::has_trivial_assignment_operator + _Trivial; + return __copy_aux2(__first, __last, + __result, + _Trivial()); + } + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy_ni1(_InputIter __first, _InputIter __last, + _OutputIter __result, __true_type) + { + typedef typename _Is_normal_iterator<_OutputIter>::_Normal __Normal; + return __copy_ni2(__first.base(), __last.base(), __result, __Normal()); + } + + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + __copy_ni1(_InputIter __first, _InputIter __last, + _OutputIter __result, __false_type) + { + typedef typename _Is_normal_iterator<_OutputIter>::_Normal __Normal; + return __copy_ni2(__first, __last, __result, __Normal()); + } + + /** + * @brief Copies the range [first,last) into result. + * @param first An input iterator. + * @param last An input iterator. + * @param result An output iterator. + * @return result + (first - last) + * + * This inline function will boil down to a call to @c memmove whenever + * possible. Failing that, if random access iterators are passed, then the + * loop count will be known (and therefore a candidate for compiler + * optimizations such as unrolling). If the input range and the output + * range overlap, then the copy_backward function should be used instead. + */ + template<typename _InputIter, typename _OutputIter> + inline _OutputIter + copy(_InputIter __first, _InputIter __last, _OutputIter __result) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter>) + __glibcpp_function_requires(_OutputIteratorConcept<_OutputIter, + typename iterator_traits<_InputIter>::value_type>) + + typedef typename _Is_normal_iterator<_InputIter>::_Normal __Normal; + return __copy_ni1(__first, __last, __result, __Normal()); + } + + //-------------------------------------------------- + // copy_backward + + template<typename _BidirectionalIter1, typename _BidirectionalIter2> + inline _BidirectionalIter2 + __copy_backward(_BidirectionalIter1 __first, _BidirectionalIter1 __last, + _BidirectionalIter2 __result, + bidirectional_iterator_tag) + { + while (__first != __last) + *--__result = *--__last; + return __result; + } + + template<typename _RandomAccessIter, typename _BidirectionalIter> + inline _BidirectionalIter + __copy_backward(_RandomAccessIter __first, _RandomAccessIter __last, + _BidirectionalIter __result, + random_access_iterator_tag) + { + typename iterator_traits<_RandomAccessIter>::difference_type __n; + for (__n = __last - __first; __n > 0; --__n) + *--__result = *--__last; + return __result; + } + + + // This dispatch class is a workaround for compilers that do not + // have partial ordering of function templates. All we're doing is + // creating a specialization so that we can turn a call to copy_backward + // into a memmove whenever possible. + + template<typename _BidirectionalIter1, typename _BidirectionalIter2, + typename _BoolType> + struct __copy_backward_dispatch + { + static _BidirectionalIter2 + copy(_BidirectionalIter1 __first, _BidirectionalIter1 __last, + _BidirectionalIter2 __result) + { + return __copy_backward(__first, __last, + __result, + __iterator_category(__first)); + } + }; + + template<typename _Tp> + struct __copy_backward_dispatch<_Tp*, _Tp*, __true_type> + { + static _Tp* + copy(const _Tp* __first, const _Tp* __last, _Tp* __result) + { + const ptrdiff_t _Num = __last - __first; + memmove(__result - _Num, __first, sizeof(_Tp) * _Num); + return __result - _Num; + } + }; + + template<typename _Tp> + struct __copy_backward_dispatch<const _Tp*, _Tp*, __true_type> + { + static _Tp* + copy(const _Tp* __first, const _Tp* __last, _Tp* __result) + { + return __copy_backward_dispatch<_Tp*, _Tp*, __true_type> + ::copy(__first, __last, __result); + } + }; + + template<typename _BI1, typename _BI2> + inline _BI2 + __copy_backward_aux(_BI1 __first, _BI1 __last, _BI2 __result) + { + typedef typename __type_traits<typename iterator_traits<_BI2>::value_type> + ::has_trivial_assignment_operator _Trivial; + return __copy_backward_dispatch<_BI1, _BI2, _Trivial> + ::copy(__first, __last, __result); + } + + template <typename _BI1, typename _BI2> + inline _BI2 + __copy_backward_output_normal_iterator(_BI1 __first, _BI1 __last, + _BI2 __result, __true_type) + { return _BI2(__copy_backward_aux(__first, __last, __result.base())); } + + template <typename _BI1, typename _BI2> + inline _BI2 + __copy_backward_output_normal_iterator(_BI1 __first, _BI1 __last, + _BI2 __result, __false_type) + { return __copy_backward_aux(__first, __last, __result); } + + template <typename _BI1, typename _BI2> + inline _BI2 + __copy_backward_input_normal_iterator(_BI1 __first, _BI1 __last, + _BI2 __result, __true_type) + { + typedef typename _Is_normal_iterator<_BI2>::_Normal __Normal; + return __copy_backward_output_normal_iterator(__first.base(), __last.base(), + __result, __Normal()); + } + + template <typename _BI1, typename _BI2> + inline _BI2 + __copy_backward_input_normal_iterator(_BI1 __first, _BI1 __last, + _BI2 __result, __false_type) + { + typedef typename _Is_normal_iterator<_BI2>::_Normal __Normal; + return __copy_backward_output_normal_iterator(__first, __last, __result, + __Normal()); + } + + /** + * @brief Copies the range [first,last) into result. + * @param first An input iterator. + * @param last An input iterator. + * @param result An output iterator. + * @return result - (first - last) + * + * The function has the same effect as copy, but starts at the end of the + * range and works its way to the start, returning the start of the result. + * This inline function will boil down to a call to @c memmove whenever + * possible. Failing that, if random access iterators are passed, then the + * loop count will be known (and therefore a candidate for compiler + * optimizations such as unrolling). + */ + template <typename _BI1, typename _BI2> + inline _BI2 + copy_backward(_BI1 __first, _BI1 __last, _BI2 __result) + { + // concept requirements + __glibcpp_function_requires(_BidirectionalIteratorConcept<_BI1>) + __glibcpp_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>) + __glibcpp_function_requires(_ConvertibleConcept< + typename iterator_traits<_BI1>::value_type, + typename iterator_traits<_BI2>::value_type>) + + typedef typename _Is_normal_iterator<_BI1>::_Normal __Normal; + return __copy_backward_input_normal_iterator(__first, __last, __result, + __Normal()); + } + + + //-------------------------------------------------- + // fill and fill_n + + + /** + * @brief Fills the range [first,last) with copies of value. + * @param first A forward iterator. + * @param last A forward iterator. + * @param value A reference-to-const of arbitrary type. + * @return Nothing. + * + * This function fills a range with copies of the same value. For one-byte + * types filling contiguous areas of memory, this becomes an inline call to + * @c memset. + */ + template<typename _ForwardIter, typename _Tp> + void + fill(_ForwardIter __first, _ForwardIter __last, const _Tp& __value) + { + // concept requirements + __glibcpp_function_requires(_Mutable_ForwardIteratorConcept<_ForwardIter>) + + for ( ; __first != __last; ++__first) + *__first = __value; + } + + /** + * @brief Fills the range [first,first+n) with copies of value. + * @param first An output iterator. + * @param n The count of copies to perform. + * @param value A reference-to-const of arbitrary type. + * @return The iterator at first+n. + * + * This function fills a range with copies of the same value. For one-byte + * types filling contiguous areas of memory, this becomes an inline call to + * @c memset. + */ + template<typename _OutputIter, typename _Size, typename _Tp> + _OutputIter + fill_n(_OutputIter __first, _Size __n, const _Tp& __value) + { + // concept requirements + __glibcpp_function_requires(_OutputIteratorConcept<_OutputIter,_Tp>) + + for ( ; __n > 0; --__n, ++__first) + *__first = __value; + return __first; + } + + // Specialization: for one-byte types we can use memset. + + inline void + fill(unsigned char* __first, unsigned char* __last, const unsigned char& __c) + { + unsigned char __tmp = __c; + memset(__first, __tmp, __last - __first); + } + + inline void + fill(signed char* __first, signed char* __last, const signed char& __c) + { + signed char __tmp = __c; + memset(__first, static_cast<unsigned char>(__tmp), __last - __first); + } + + inline void + fill(char* __first, char* __last, const char& __c) + { + char __tmp = __c; + memset(__first, static_cast<unsigned char>(__tmp), __last - __first); + } + + template<typename _Size> + inline unsigned char* + fill_n(unsigned char* __first, _Size __n, const unsigned char& __c) + { + fill(__first, __first + __n, __c); + return __first + __n; + } + + template<typename _Size> + inline signed char* + fill_n(char* __first, _Size __n, const signed char& __c) + { + fill(__first, __first + __n, __c); + return __first + __n; + } + + template<typename _Size> + inline char* + fill_n(char* __first, _Size __n, const char& __c) + { + fill(__first, __first + __n, __c); + return __first + __n; + } + + + //-------------------------------------------------- + // equal and mismatch + + /** + * @brief Finds the places in ranges which don't match. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @return A pair of iterators pointing to the first mismatch. + * + * This compares the elements of two ranges using @c == and returns a pair + * of iterators. The first iterator points into the first range, the + * second iterator points into the second range, and the elements pointed + * to by the iterators are not equal. + */ + template<typename _InputIter1, typename _InputIter2> + pair<_InputIter1, _InputIter2> + mismatch(_InputIter1 __first1, _InputIter1 __last1, + _InputIter2 __first2) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter1>) + __glibcpp_function_requires(_InputIteratorConcept<_InputIter2>) + __glibcpp_function_requires(_EqualityComparableConcept< + typename iterator_traits<_InputIter1>::value_type>) + __glibcpp_function_requires(_EqualityComparableConcept< + typename iterator_traits<_InputIter2>::value_type>) + + while (__first1 != __last1 && *__first1 == *__first2) { + ++__first1; + ++__first2; + } + return pair<_InputIter1, _InputIter2>(__first1, __first2); + } + + /** + * @brief Finds the places in ranges which don't match. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @param binary_pred A binary predicate @link s20_3_1_base functor@endlink. + * @return A pair of iterators pointing to the first mismatch. + * + * This compares the elements of two ranges using the binary_pred + * parameter, and returns a pair + * of iterators. The first iterator points into the first range, the + * second iterator points into the second range, and the elements pointed + * to by the iterators are not equal. + */ + template<typename _InputIter1, typename _InputIter2, typename _BinaryPredicate> + pair<_InputIter1, _InputIter2> + mismatch(_InputIter1 __first1, _InputIter1 __last1, + _InputIter2 __first2, + _BinaryPredicate __binary_pred) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter1>) + __glibcpp_function_requires(_InputIteratorConcept<_InputIter2>) + + while (__first1 != __last1 && __binary_pred(*__first1, *__first2)) { + ++__first1; + ++__first2; + } + return pair<_InputIter1, _InputIter2>(__first1, __first2); + } + + /** + * @brief Tests a range for element-wise equality. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @return A boolean true or false. + * + * This compares the elements of two ranges using @c == and returns true or + * false depending on whether all of the corresponding elements of the + * ranges are equal. + */ + template<typename _InputIter1, typename _InputIter2> + inline bool + equal(_InputIter1 __first1, _InputIter1 __last1, + _InputIter2 __first2) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter1>) + __glibcpp_function_requires(_InputIteratorConcept<_InputIter2>) + __glibcpp_function_requires(_EqualOpConcept< + typename iterator_traits<_InputIter1>::value_type, + typename iterator_traits<_InputIter2>::value_type>) + + for ( ; __first1 != __last1; ++__first1, ++__first2) + if (!(*__first1 == *__first2)) + return false; + return true; + } + + /** + * @brief Tests a range for element-wise equality. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @param binary_pred A binary predicate @link s20_3_1_base functor@endlink. + * @return A boolean true or false. + * + * This compares the elements of two ranges using the binary_pred + * parameter, and returns true or + * false depending on whether all of the corresponding elements of the + * ranges are equal. + */ + template<typename _InputIter1, typename _InputIter2, typename _BinaryPredicate> + inline bool + equal(_InputIter1 __first1, _InputIter1 __last1, + _InputIter2 __first2, + _BinaryPredicate __binary_pred) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter1>) + __glibcpp_function_requires(_InputIteratorConcept<_InputIter2>) + + for ( ; __first1 != __last1; ++__first1, ++__first2) + if (!__binary_pred(*__first1, *__first2)) + return false; + return true; + } + + //-------------------------------------------------- + // lexicographical_compare + + /** + * @brief Performs "dictionary" comparison on ranges. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @param last2 An input iterator. + * @return A boolean true or false. + * + * "Returns true if the sequence of elements defined by the range + * [first1,last1) is lexicographically less than the sequence of elements + * defined by the range [first2,last2). Returns false otherwise." + * (Quoted from [25.3.8]/1.) If the iterators are all character pointers, + * then this is an inline call to @c memcmp. + */ + template<typename _InputIter1, typename _InputIter2> + bool + lexicographical_compare(_InputIter1 __first1, _InputIter1 __last1, + _InputIter2 __first2, _InputIter2 __last2) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter1>) + __glibcpp_function_requires(_InputIteratorConcept<_InputIter2>) + __glibcpp_function_requires(_LessThanComparableConcept< + typename iterator_traits<_InputIter1>::value_type>) + __glibcpp_function_requires(_LessThanComparableConcept< + typename iterator_traits<_InputIter2>::value_type>) + + for ( ; __first1 != __last1 && __first2 != __last2 + ; ++__first1, ++__first2) { + if (*__first1 < *__first2) + return true; + if (*__first2 < *__first1) + return false; + } + return __first1 == __last1 && __first2 != __last2; + } + + /** + * @brief Performs "dictionary" comparison on ranges. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @param last2 An input iterator. + * @param comp A @link s20_3_3_comparisons comparison functor@endlink. + * @return A boolean true or false. + * + * The same as the four-parameter @c lexigraphical_compare, but uses the + * comp parameter instead of @c <. + */ + template<typename _InputIter1, typename _InputIter2, typename _Compare> + bool + lexicographical_compare(_InputIter1 __first1, _InputIter1 __last1, + _InputIter2 __first2, _InputIter2 __last2, + _Compare __comp) + { + // concept requirements + __glibcpp_function_requires(_InputIteratorConcept<_InputIter1>) + __glibcpp_function_requires(_InputIteratorConcept<_InputIter2>) + + for ( ; __first1 != __last1 && __first2 != __last2 + ; ++__first1, ++__first2) { + if (__comp(*__first1, *__first2)) + return true; + if (__comp(*__first2, *__first1)) + return false; + } + return __first1 == __last1 && __first2 != __last2; + } + + inline bool + lexicographical_compare(const unsigned char* __first1, const unsigned char* __last1, + const unsigned char* __first2, const unsigned char* __last2) + { + const size_t __len1 = __last1 - __first1; + const size_t __len2 = __last2 - __first2; + const int __result = memcmp(__first1, __first2, min(__len1, __len2)); + return __result != 0 ? __result < 0 : __len1 < __len2; + } + + inline bool + lexicographical_compare(const char* __first1, const char* __last1, + const char* __first2, const char* __last2) + { +#if CHAR_MAX == SCHAR_MAX + return lexicographical_compare((const signed char*) __first1, + (const signed char*) __last1, + (const signed char*) __first2, + (const signed char*) __last2); +#else /* CHAR_MAX == SCHAR_MAX */ + return lexicographical_compare((const unsigned char*) __first1, + (const unsigned char*) __last1, + (const unsigned char*) __first2, + (const unsigned char*) __last2); +#endif /* CHAR_MAX == SCHAR_MAX */ + } + +} // namespace std + +#endif /* __GLIBCPP_INTERNAL_ALGOBASE_H */ + +// Local Variables: +// mode:C++ +// End: |
