1/*
2 Copyright (c) Marshall Clow 2008-2012.
3
4 Distributed under the Boost Software License, Version 1.0. (See accompanying
5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6*/
7
8/// \file equal.hpp
9/// \brief Test ranges to if they are equal
10/// \author Marshall Clow
11
12#ifndef BOOST_ALGORITHM_EQUAL_HPP
13#define BOOST_ALGORITHM_EQUAL_HPP
14
15#include <algorithm> // for std::equal
16#include <functional> // for std::equal_to
17
18namespace boost { namespace algorithm {
19
20namespace detail {
21
22 template <class T1, class T2>
23 struct eq : public std::binary_function<T1, T2, bool> {
24 bool operator () ( const T1& v1, const T2& v2 ) const { return v1 == v2 ;}
25 };
26
27 template <class RandomAccessIterator1, class RandomAccessIterator2, class BinaryPredicate>
28 bool equal ( RandomAccessIterator1 first1, RandomAccessIterator1 last1,
29 RandomAccessIterator2 first2, RandomAccessIterator2 last2, BinaryPredicate pred,
30 std::random_access_iterator_tag, std::random_access_iterator_tag )
31 {
32 // Random-access iterators let is check the sizes in constant time
33 if ( std::distance ( first1, last1 ) != std::distance ( first2, last2 ))
34 return false;
35 // If we know that the sequences are the same size, the original version is fine
36 return std::equal ( first1, last1, first2, pred );
37 }
38
39 template <class InputIterator1, class InputIterator2, class BinaryPredicate>
40 bool equal ( InputIterator1 first1, InputIterator1 last1,
41 InputIterator2 first2, InputIterator2 last2, BinaryPredicate pred,
42 std::input_iterator_tag, std::input_iterator_tag )
43 {
44 for (; first1 != last1 && first2 != last2; ++first1, ++first2 )
45 if ( !pred(*first1, *first2 ))
46 return false;
47
48 return first1 == last1 && first2 == last2;
49 }
50}
51
52/// \fn equal ( InputIterator1 first1, InputIterator1 last1,
53/// InputIterator2 first2, InputIterator2 last2,
54/// BinaryPredicate pred )
55/// \return true if all elements in the two ranges are equal
56///
57/// \param first1 The start of the first range.
58/// \param last1 One past the end of the first range.
59/// \param first2 The start of the second range.
60/// \param last2 One past the end of the second range.
61/// \param pred A predicate for comparing the elements of the ranges
62template <class InputIterator1, class InputIterator2, class BinaryPredicate>
63bool equal ( InputIterator1 first1, InputIterator1 last1,
64 InputIterator2 first2, InputIterator2 last2, BinaryPredicate pred )
65{
66 return boost::algorithm::detail::equal (
67 first1, last1, first2, last2, pred,
68 typename std::iterator_traits<InputIterator1>::iterator_category (),
69 typename std::iterator_traits<InputIterator2>::iterator_category ());
70}
71
72/// \fn equal ( InputIterator1 first1, InputIterator1 last1,
73/// InputIterator2 first2, InputIterator2 last2 )
74/// \return true if all elements in the two ranges are equal
75///
76/// \param first1 The start of the first range.
77/// \param last1 One past the end of the first range.
78/// \param first2 The start of the second range.
79/// \param last2 One past the end of the second range.
80template <class InputIterator1, class InputIterator2>
81bool equal ( InputIterator1 first1, InputIterator1 last1,
82 InputIterator2 first2, InputIterator2 last2 )
83{
84 return boost::algorithm::detail::equal (
85 first1, last1, first2, last2,
86 boost::algorithm::detail::eq<
87 typename std::iterator_traits<InputIterator1>::value_type,
88 typename std::iterator_traits<InputIterator2>::value_type> (),
89 typename std::iterator_traits<InputIterator1>::iterator_category (),
90 typename std::iterator_traits<InputIterator2>::iterator_category ());
91}
92
93// There are already range-based versions of these.
94
95}} // namespace boost and algorithm
96
97#endif // BOOST_ALGORITHM_EQUAL_HPP
98