1// Copyright Kevlin Henney, 2000-2005.
2// Copyright Alexander Nasonov, 2006-2010.
3// Copyright Antony Polukhin, 2011-2024.
4//
5// Distributed under the Boost Software License, Version 1.0. (See
6// accompanying file LICENSE_1_0.txt or copy at
7// http://www.boost.org/LICENSE_1_0.txt)
8//
9// what: lexical_cast custom keyword cast
10// who: contributed by Kevlin Henney,
11// enhanced with contributions from Terje Slettebo,
12// with additional fixes and suggestions from Gennaro Prota,
13// Beman Dawes, Dave Abrahams, Daryle Walker, Peter Dimov,
14// Alexander Nasonov, Antony Polukhin, Justin Viiret, Michael Hofmann,
15// Cheng Yang, Matthew Bradbury, David W. Birdsall, Pavel Korzh and other Boosters
16// when: November 2000, March 2003, June 2005, June 2006, March 2011 - 2014
17
18#ifndef BOOST_LEXICAL_CAST_DETAIL_IS_CHARACTER_HPP
19#define BOOST_LEXICAL_CAST_DETAIL_IS_CHARACTER_HPP
20
21#include <boost/config.hpp>
22#ifdef BOOST_HAS_PRAGMA_ONCE
23# pragma once
24#endif
25
26#include <boost/type_traits/integral_constant.hpp>
27#include <boost/type_traits/is_same.hpp>
28
29namespace boost { namespace detail {
30
31// returns true, if T is one of the character types
32template < typename T >
33using is_character = boost::integral_constant<
34 bool,
35 boost::is_same< T, char >::value ||
36#if !defined(BOOST_NO_STRINGSTREAM) && !defined(BOOST_NO_STD_WSTRING)
37 boost::is_same< T, wchar_t >::value ||
38#endif
39#ifndef BOOST_NO_CXX11_CHAR16_T
40 boost::is_same< T, char16_t >::value ||
41#endif
42#ifndef BOOST_NO_CXX11_CHAR32_T
43 boost::is_same< T, char32_t >::value ||
44#endif
45 boost::is_same< T, unsigned char >::value ||
46 boost::is_same< T, signed char >::value
47>;
48
49}}
50
51#endif // BOOST_LEXICAL_CAST_DETAIL_IS_CHARACTER_HPP
52
53

source code of boost/libs/lexical_cast/include/boost/lexical_cast/detail/is_character.hpp