1 | // Copyright (C) 2007, 2008 Steven Watanabe, Joseph Gauterin, Niels Dekker |
---|
2 | // |
---|
3 | // Distributed under the Boost Software License, Version 1.0. (See |
---|
4 | // accompanying file LICENSE_1_0.txt or copy at |
---|
5 | // http://www.boost.org/LICENSE_1_0.txt) |
---|
6 | // For more information, see http://www.boost.org |
---|
7 | |
---|
8 | |
---|
9 | #ifndef BOOST_UTILITY_SWAP_HPP |
---|
10 | #define BOOST_UTILITY_SWAP_HPP |
---|
11 | |
---|
12 | // Note: the implementation of this utility contains various workarounds: |
---|
13 | // - swap_impl is put outside the boost namespace, to avoid infinite |
---|
14 | // recursion (causing stack overflow) when swapping objects of a primitive |
---|
15 | // type. |
---|
16 | // - swap_impl has a using-directive, rather than a using-declaration, |
---|
17 | // because some compilers (including MSVC 7.1, Borland 5.9.3, and |
---|
18 | // Intel 8.1) don't do argument-dependent lookup when it has a |
---|
19 | // using-declaration instead. |
---|
20 | // - boost::swap has two template arguments, instead of one, to |
---|
21 | // avoid ambiguity when swapping objects of a Boost type that does |
---|
22 | // not have its own boost::swap overload. |
---|
23 | |
---|
24 | #include <algorithm> //for std::swap |
---|
25 | #include <cstddef> //for std::size_t |
---|
26 | |
---|
27 | namespace boost_swap_impl |
---|
28 | { |
---|
29 | template<class T> |
---|
30 | void swap_impl(T& left, T& right) |
---|
31 | { |
---|
32 | using namespace std;//use std::swap if argument dependent lookup fails |
---|
33 | swap(left,right); |
---|
34 | } |
---|
35 | |
---|
36 | template<class T, std::size_t N> |
---|
37 | void swap_impl(T (& left)[N], T (& right)[N]) |
---|
38 | { |
---|
39 | for (std::size_t i = 0; i < N; ++i) |
---|
40 | { |
---|
41 | ::boost_swap_impl::swap_impl(left[i], right[i]); |
---|
42 | } |
---|
43 | } |
---|
44 | } |
---|
45 | |
---|
46 | namespace boost |
---|
47 | { |
---|
48 | template<class T1, class T2> |
---|
49 | void swap(T1& left, T2& right) |
---|
50 | { |
---|
51 | ::boost_swap_impl::swap_impl(left, right); |
---|
52 | } |
---|
53 | } |
---|
54 | |
---|
55 | #endif |
---|