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