sl@0: // (C) Copyright David Abrahams 2002.
sl@0: // (C) Copyright Jeremy Siek    2002.
sl@0: // (C) Copyright Thomas Witt    2002.
sl@0: // Distributed under the Boost Software License, Version 1.0. (See
sl@0: // accompanying file LICENSE_1_0.txt or copy at
sl@0: // http://www.boost.org/LICENSE_1_0.txt)
sl@0: #ifndef BOOST_INTEROPERABLE_23022003THW_HPP
sl@0: # define BOOST_INTEROPERABLE_23022003THW_HPP
sl@0: 
sl@0: # include <boost/mpl/bool.hpp>
sl@0: # include <boost/mpl/or.hpp>
sl@0: 
sl@0: # include <boost/type_traits/is_convertible.hpp>
sl@0: 
sl@0: # include <boost/iterator/detail/config_def.hpp> // must appear last
sl@0: 
sl@0: namespace boost
sl@0: {
sl@0: 
sl@0:   //
sl@0:   // Meta function that determines whether two
sl@0:   // iterator types are considered interoperable.
sl@0:   //
sl@0:   // Two iterator types A,B are considered interoperable if either
sl@0:   // A is convertible to B or vice versa.
sl@0:   // This interoperability definition is in sync with the
sl@0:   // standards requirements on constant/mutable container
sl@0:   // iterators (23.1 [lib.container.requirements]).
sl@0:   //
sl@0:   // For compilers that don't support is_convertible 
sl@0:   // is_interoperable gives false positives. See comments
sl@0:   // on operator implementation for consequences.
sl@0:   //
sl@0:   template <typename A, typename B>
sl@0:   struct is_interoperable
sl@0: # ifdef BOOST_NO_STRICT_ITERATOR_INTEROPERABILITY
sl@0:     : mpl::true_
sl@0: # else
sl@0:     : mpl::or_<
sl@0:           is_convertible< A, B >
sl@0:         , is_convertible< B, A > >
sl@0: # endif
sl@0:   { 
sl@0:   };
sl@0: 
sl@0: } // namespace boost
sl@0: 
sl@0: # include <boost/iterator/detail/config_undef.hpp>
sl@0: 
sl@0: #endif // BOOST_INTEROPERABLE_23022003THW_HPP