1
2// (C) Copyright Dave Abrahams, Steve Cleary, Beman Dawes,
3// Howard Hinnant and John Maddock 2000.
4// (C) Copyright Mat Marcus, Jesse Jones and Adobe Systems Inc 2001
5
6// Use, modification and distribution are subject to the Boost Software License,
7// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
8// http://www.boost.org/LICENSE_1_0.txt).
9//
10// See http://www.boost.org/libs/type_traits for most recent version including documentation.
11
12// Fixed is_pointer, is_lvalue_reference, is_const, is_volatile, is_same,
13// is_member_pointer based on the Simulated Partial Specialization work
14// of Mat Marcus and Jesse Jones. See http://opensource.adobe.com or
15// http://groups.yahoo.com/group/boost/message/5441
16// Some workarounds in here use ideas suggested from "Generic<Programming>:
17// Mappings between Types and Values"
18// by Andrei Alexandrescu (see http://www.cuj.com/experts/1810/alexandr.html).
19
20
21#ifndef BOOST_TT_IS_LVALUE_REFERENCE_HPP_INCLUDED
22#define BOOST_TT_IS_LVALUE_REFERENCE_HPP_INCLUDED
23
24#include <boost/type_traits/integral_constant.hpp>
25
26namespace boost {
27
28#if defined( BOOST_CODEGEARC )
29 template <class T> struct is_lvalue_reference : public integral_constant<bool, __is_reference(T)>{};
30#else
31
32 template <class T> struct is_lvalue_reference : public false_type{};
33 template <class T> struct is_lvalue_reference<T&> : public true_type{};
34
35#if defined(BOOST_ILLEGAL_CV_REFERENCES)
36// these are illegal specialisations; cv-qualifies applied to
37// references have no effect according to [8.3.2p1],
38// C++ Builder requires them though as it treats cv-qualified
39// references as distinct types...
40 template <class T> struct is_lvalue_reference<T&const> : public true_type{};
41 template <class T> struct is_lvalue_reference<T&volatile> : public true_type{};
42 template <class T> struct is_lvalue_reference<T&const volatile> : public true_type{};
43#endif
44
45#endif
46
47} // namespace boost
48
49#endif // BOOST_TT_IS_REFERENCE_HPP_INCLUDED
50
51

source code of include/boost/type_traits/is_lvalue_reference.hpp