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// Copyright Kevlin Henney, 2000-2005.
// Copyright Alexander Nasonov, 2006-2010.
// Copyright Antony Polukhin, 2011-2024.
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// what:  lexical_cast custom keyword cast
// who:   contributed by Kevlin Henney,
//        enhanced with contributions from Terje Slettebo,
//        with additional fixes and suggestions from Gennaro Prota,
//        Beman Dawes, Dave Abrahams, Daryle Walker, Peter Dimov,
//        Alexander Nasonov, Antony Polukhin, Justin Viiret, Michael Hofmann,
//        Cheng Yang, Matthew Bradbury, David W. Birdsall, Pavel Korzh and other Boosters
// when:  November 2000, March 2003, June 2005, June 2006, March 2011 - 2014


#include <boost/config.hpp>
#   pragma once

#include <boost/type_traits/integral_constant.hpp>
#include <boost/type_traits/is_same.hpp>

namespace boost { namespace detail {

// returns true, if T is one of the character types
template < typename T >
using is_character = boost::integral_constant<
    boost::is_same< T, char >::value ||
    boost::is_same< T, wchar_t >::value ||
#ifndef BOOST_NO_CXX11_CHAR16_T
    boost::is_same< T, char16_t >::value ||
#ifndef BOOST_NO_CXX11_CHAR32_T
    boost::is_same< T, char32_t >::value ||
    boost::is_same< T, unsigned char >::value ||
    boost::is_same< T, signed char >::value