williamr@2: /* Copyright 2003-2005 Joaquín M López Muñoz.
williamr@2:  * Distributed under the Boost Software License, Version 1.0.
williamr@2:  * (See accompanying file LICENSE_1_0.txt or copy at
williamr@2:  * http://www.boost.org/LICENSE_1_0.txt)
williamr@2:  *
williamr@2:  * See http://www.boost.org/libs/multi_index for library home page.
williamr@2:  */
williamr@2: 
williamr@2: #ifndef BOOST_MULTI_INDEX_DETAIL_PREVENT_ETI_HPP
williamr@2: #define BOOST_MULTI_INDEX_DETAIL_PREVENT_ETI_HPP
williamr@2: 
williamr@2: #if defined(_MSC_VER)&&(_MSC_VER>=1200)
williamr@2: #pragma once
williamr@2: #endif
williamr@2: 
williamr@2: #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
williamr@2: #include <boost/detail/workaround.hpp>
williamr@2: 
williamr@2: #if BOOST_WORKAROUND(BOOST_MSVC,<1300)
williamr@2: #include <boost/mpl/if.hpp>
williamr@2: #include <boost/mpl/integral_c.hpp>
williamr@2: #include <boost/mpl/aux_/msvc_never_true.hpp>
williamr@2: #endif
williamr@2: 
williamr@2: namespace boost{
williamr@2: 
williamr@2: namespace multi_index{
williamr@2: 
williamr@2: namespace detail{
williamr@2: 
williamr@2: #if BOOST_WORKAROUND(BOOST_MSVC,<1300)
williamr@2: /* See
williamr@2:  * http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?Effective_MPL
williamr@2:  * Item 5.6, Beware of the 'early template instantiation' trap.
williamr@2:  */
williamr@2: 
williamr@2: template<typename Type,typename Construct>
williamr@2: struct prevent_eti
williamr@2: {
williamr@2:   typedef typename mpl::if_<
williamr@2:     mpl::aux::msvc_never_true<Type>,
williamr@2:     mpl::integral_c<int,0>,
williamr@2:     Construct
williamr@2:   >::type type;
williamr@2: };
williamr@2: #else
williamr@2: template<typename Type,typename Construct>
williamr@2: struct prevent_eti
williamr@2: {
williamr@2:   typedef Construct type;
williamr@2: };
williamr@2: #endif
williamr@2: 
williamr@2: } /* namespace multi_index::detail */
williamr@2: 
williamr@2: } /* namespace multi_index */
williamr@2: 
williamr@2: } /* namespace boost */
williamr@2: 
williamr@2: #endif