1 /*
2  *          Copyright Andrey Semashev 2007 - 2015.
3  * Distributed under the Boost Software License, Version 1.0.
4  *    (See accompanying file LICENSE_1_0.txt or copy at
5  *          http://www.boost.org/LICENSE_1_0.txt)
6  */
7 /*!
8  * \file   deduce_char_type.hpp
9  * \author Andrey Semashev
10  * \date   17.11.2012
11  *
12  * \brief  This header is the Boost.Log library implementation, see the library documentation
13  *         at http://www.boost.org/doc/libs/release/libs/log/doc/html/index.html.
14  */
15 
16 #ifndef BOOST_LOG_DETAIL_DEDUCE_CHAR_TYPE_HPP_INCLUDED_
17 #define BOOST_LOG_DETAIL_DEDUCE_CHAR_TYPE_HPP_INCLUDED_
18 
19 #include <boost/log/detail/config.hpp>
20 #include <boost/log/detail/header.hpp>
21 
22 #ifdef BOOST_HAS_PRAGMA_ONCE
23 #pragma once
24 #endif
25 
26 namespace boost {
27 
28 BOOST_LOG_OPEN_NAMESPACE
29 
30 namespace aux {
31 
32 template< typename T >
33 struct deduced_char_type;
34 
35 template< >
36 struct deduced_char_type< char >
37 {
38     typedef char type;
39 };
40 
41 template< >
42 struct deduced_char_type< const char >
43 {
44     typedef char type;
45 };
46 
47 template< >
48 struct deduced_char_type< wchar_t >
49 {
50     typedef wchar_t type;
51 };
52 
53 template< >
54 struct deduced_char_type< const wchar_t >
55 {
56     typedef wchar_t type;
57 };
58 
59 //! Auxiliary traits to detect character type from a string
60 template< typename RangeT >
61 struct deduce_char_type :
62     public deduced_char_type< typename RangeT::value_type >
63 {
64 };
65 
66 template< typename T >
67 struct deduce_char_type< T* > :
68     public deduced_char_type< T >
69 {
70 };
71 
72 template< typename T >
73 struct deduce_char_type< T* const > :
74     public deduced_char_type< T >
75 {
76 };
77 
78 template< typename T, unsigned int CountV >
79 struct deduce_char_type< T[CountV] > :
80     public deduced_char_type< T >
81 {
82 };
83 
84 template< typename T >
85 struct deduce_char_type< T& > :
86     public deduce_char_type< T >
87 {
88 };
89 
90 #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
91 
92 template< typename T >
93 struct deduce_char_type< T&& > :
94     public deduce_char_type< T >
95 {
96 };
97 
98 #endif
99 
100 } // namespace aux
101 
102 BOOST_LOG_CLOSE_NAMESPACE // namespace log
103 
104 } // namespace boost
105 
106 #include <boost/log/detail/footer.hpp>
107 
108 #endif // BOOST_LOG_DETAIL_DEDUCE_CHAR_TYPE_HPP_INCLUDED_
109