1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/ossrv/ossrv_pub/boost_apis/boost/python/pure_virtual.hpp	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,124 @@
     1.4 +// Copyright David Abrahams 2003.
     1.5 +// Distributed under the Boost Software License, Version 1.0. (See
     1.6 +// accompanying file LICENSE_1_0.txt or copy at
     1.7 +// http://www.boost.org/LICENSE_1_0.txt)
     1.8 +#ifndef PURE_VIRTUAL_DWA2003810_HPP
     1.9 +# define PURE_VIRTUAL_DWA2003810_HPP
    1.10 +
    1.11 +# include <boost/python/def_visitor.hpp>
    1.12 +# include <boost/python/default_call_policies.hpp>
    1.13 +# include <boost/mpl/push_front.hpp>
    1.14 +# include <boost/mpl/pop_front.hpp>
    1.15 +
    1.16 +# include <boost/python/detail/nullary_function_adaptor.hpp>
    1.17 +
    1.18 +namespace boost { namespace python { 
    1.19 +
    1.20 +namespace detail
    1.21 +{
    1.22 +  //
    1.23 +  // @group Helpers for pure_virtual_visitor. {
    1.24 +  //
    1.25 +  
    1.26 +  // Raises a Python RuntimeError reporting that a pure virtual
    1.27 +  // function was called.
    1.28 +  void BOOST_PYTHON_DECL pure_virtual_called();
    1.29 +
    1.30 +  // Replace the two front elements of S with T1 and T2
    1.31 +  template <class S, class T1, class T2>
    1.32 +  struct replace_front2
    1.33 +  {
    1.34 +      // Metafunction forwarding seemed to confound vc6 
    1.35 +      typedef typename mpl::push_front<
    1.36 +          typename mpl::push_front<
    1.37 +              typename mpl::pop_front<
    1.38 +                  typename mpl::pop_front<
    1.39 +                      S
    1.40 +                  >::type
    1.41 +              >::type
    1.42 +            , T2
    1.43 +          >::type
    1.44 +        , T1
    1.45 +      >::type type;
    1.46 +  };
    1.47 +
    1.48 +  // Given an MPL sequence representing a member function [object]
    1.49 +  // signature, returns a new MPL sequence whose return type is
    1.50 +  // replaced by void, and whose first argument is replaced by C&.
    1.51 +  template <class C, class S>
    1.52 +  typename replace_front2<S,void,C&>::type
    1.53 +  error_signature(S BOOST_APPEND_EXPLICIT_TEMPLATE_TYPE(C))
    1.54 +  {
    1.55 +      typedef typename replace_front2<S,void,C&>::type r;
    1.56 +      return r();
    1.57 +  }
    1.58 +
    1.59 +  //
    1.60 +  // } 
    1.61 +  //
    1.62 +
    1.63 +  //
    1.64 +  // A def_visitor which defines a method as usual, then adds a
    1.65 +  // corresponding function which raises a "pure virtual called"
    1.66 +  // exception unless it's been overridden.
    1.67 +  //
    1.68 +  template <class PointerToMemberFunction>
    1.69 +  struct pure_virtual_visitor
    1.70 +    : def_visitor<pure_virtual_visitor<PointerToMemberFunction> >
    1.71 +  {
    1.72 +      pure_virtual_visitor(PointerToMemberFunction pmf)
    1.73 +        : m_pmf(pmf)
    1.74 +      {}
    1.75 +      
    1.76 +   private:
    1.77 +      friend class python::def_visitor_access;
    1.78 +      
    1.79 +      template <class C_, class Options>
    1.80 +      void visit(C_& c, char const* name, Options& options) const
    1.81 +      {
    1.82 +          // This should probably be a nicer error message
    1.83 +          BOOST_STATIC_ASSERT(!Options::has_default_implementation);
    1.84 +
    1.85 +          // Add the virtual function dispatcher
    1.86 +          c.def(
    1.87 +              name
    1.88 +            , m_pmf
    1.89 +            , options.doc()
    1.90 +            , options.keywords()
    1.91 +            , options.policies()
    1.92 +          );
    1.93 +
    1.94 +          typedef BOOST_DEDUCED_TYPENAME C_::metadata::held_type held_type;
    1.95 +          
    1.96 +          // Add the default implementation which raises the exception
    1.97 +          c.def(
    1.98 +              name
    1.99 +            , make_function(
   1.100 +                  detail::nullary_function_adaptor<void(*)()>(pure_virtual_called)
   1.101 +                , default_call_policies()
   1.102 +                , detail::error_signature<held_type>(detail::get_signature(m_pmf))
   1.103 +              )
   1.104 +          );
   1.105 +      }
   1.106 +      
   1.107 +   private: // data members
   1.108 +      PointerToMemberFunction m_pmf;
   1.109 +  };
   1.110 +}
   1.111 +
   1.112 +//
   1.113 +// Passed a pointer to member function, generates a def_visitor which
   1.114 +// creates a method that only dispatches to Python if the function has
   1.115 +// been overridden, either in C++ or in Python, raising a "pure
   1.116 +// virtual called" exception otherwise.
   1.117 +//
   1.118 +template <class PointerToMemberFunction>
   1.119 +detail::pure_virtual_visitor<PointerToMemberFunction>
   1.120 +pure_virtual(PointerToMemberFunction pmf)
   1.121 +{
   1.122 +    return detail::pure_virtual_visitor<PointerToMemberFunction>(pmf);
   1.123 +}
   1.124 +
   1.125 +}} // namespace boost::python
   1.126 +
   1.127 +#endif // PURE_VIRTUAL_DWA2003810_HPP