williamr@2: #ifndef POINTEE_DWA200415_HPP
williamr@2: # define POINTEE_DWA200415_HPP
williamr@2: 
williamr@2: //
williamr@2: // Copyright David Abrahams 2004. Use, modification and distribution is
williamr@2: // subject to the Boost Software License, Version 1.0. (See accompanying
williamr@2: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
williamr@2: //
williamr@2: // typename pointee<P>::type provides the pointee type of P.
williamr@2: //
williamr@2: // For example, it is T for T* and X for shared_ptr<X>.
williamr@2: //
williamr@2: // http://www.boost.org/libs/iterator/doc/pointee.html
williamr@2: //
williamr@2: 
williamr@2: # include <boost/detail/is_incrementable.hpp>
williamr@2: # include <boost/iterator/iterator_traits.hpp>
williamr@2: # include <boost/type_traits/add_const.hpp>
williamr@2: # include <boost/type_traits/remove_cv.hpp>
williamr@2: # include <boost/mpl/if.hpp>
williamr@2: # include <boost/mpl/eval_if.hpp>
williamr@2: 
williamr@2: namespace boost { 
williamr@2: 
williamr@2: namespace detail
williamr@2: {
williamr@2:   template <class P>
williamr@2:   struct smart_ptr_pointee
williamr@2:   {
williamr@2:       typedef typename P::element_type type;
williamr@2:   };
williamr@2: 
williamr@2:   template <class Iterator>
williamr@2:   struct iterator_pointee
williamr@2:   {
williamr@2:       typedef typename iterator_traits<Iterator>::value_type value_type;
williamr@2:       
williamr@2:       struct impl
williamr@2:       {
williamr@2:           template <class T>
williamr@2:           static char test(T const&);
williamr@2:           
williamr@2:           static char (& test(value_type&) )[2];
williamr@2:           
williamr@2:           static Iterator& x;
williamr@2:       };
williamr@2:       
williamr@2:       BOOST_STATIC_CONSTANT(bool, is_constant = sizeof(impl::test(*impl::x)) == 1);
williamr@2:       
williamr@2:       typedef typename mpl::if_c<
williamr@2: #  if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
williamr@2:           ::boost::detail::iterator_pointee<Iterator>::is_constant
williamr@2: #  else
williamr@2:           is_constant
williamr@2: #  endif 
williamr@2:         , typename add_const<value_type>::type
williamr@2:         , value_type
williamr@2:       >::type type;
williamr@2:   };
williamr@2: }
williamr@2: 
williamr@2: template <class P>
williamr@2: struct pointee
williamr@2:   : mpl::eval_if<
williamr@2:         detail::is_incrementable<P>
williamr@2:       , detail::iterator_pointee<P>
williamr@2:       , detail::smart_ptr_pointee<P>
williamr@2:     >
williamr@2: {
williamr@2: };
williamr@2:   
williamr@2: } // namespace boost
williamr@2: 
williamr@2: #endif // POINTEE_DWA200415_HPP