sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: //
sl@0: // Copyright David Abrahams 2002, Joel de Guzman, 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: //
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: #ifndef INIT_JDG20020820_HPP
sl@0: #define INIT_JDG20020820_HPP
sl@0: 
sl@0: # include <boost/python/detail/prefix.hpp>
sl@0: 
sl@0: #include <boost/python/detail/type_list.hpp>
sl@0: #include <boost/python/args_fwd.hpp>
sl@0: #include <boost/python/detail/make_keyword_range_fn.hpp>
sl@0: #include <boost/python/def_visitor.hpp>
sl@0: 
sl@0: #include <boost/mpl/if.hpp>
sl@0: #include <boost/mpl/eval_if.hpp>
sl@0: #include <boost/mpl/size.hpp>
sl@0: #include <boost/mpl/iterator_range.hpp>
sl@0: #include <boost/mpl/empty.hpp>
sl@0: #include <boost/mpl/begin_end.hpp>
sl@0: #include <boost/mpl/bool.hpp>
sl@0: #include <boost/mpl/prior.hpp>
sl@0: #include <boost/mpl/joint_view.hpp>
sl@0: #include <boost/mpl/back.hpp>
sl@0: 
sl@0: #include <boost/type_traits/is_same.hpp>
sl@0: 
sl@0: #include <boost/preprocessor/enum_params_with_a_default.hpp>
sl@0: #include <boost/preprocessor/enum_params.hpp>
sl@0: 
sl@0: #include <utility>
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: #define BOOST_PYTHON_OVERLOAD_TYPES_WITH_DEFAULT                                \
sl@0:     BOOST_PP_ENUM_PARAMS_WITH_A_DEFAULT(                                        \
sl@0:         BOOST_PYTHON_MAX_ARITY,                                                 \
sl@0:         class T,                                                                \
sl@0:         mpl::void_)                                                             \
sl@0: 
sl@0: #define BOOST_PYTHON_OVERLOAD_TYPES                                             \
sl@0:     BOOST_PP_ENUM_PARAMS_Z(1,                                                   \
sl@0:         BOOST_PYTHON_MAX_ARITY,                                                 \
sl@0:         class T)                                                                \
sl@0: 
sl@0: #define BOOST_PYTHON_OVERLOAD_ARGS                                              \
sl@0:     BOOST_PP_ENUM_PARAMS_Z(1,                                                   \
sl@0:         BOOST_PYTHON_MAX_ARITY,                                                 \
sl@0:         T)                                                                      \
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: namespace boost { namespace python {
sl@0: 
sl@0: template <BOOST_PYTHON_OVERLOAD_TYPES_WITH_DEFAULT>
sl@0: class init; // forward declaration
sl@0: 
sl@0: 
sl@0: template <BOOST_PYTHON_OVERLOAD_TYPES_WITH_DEFAULT>
sl@0: struct optional; // forward declaration
sl@0: 
sl@0: namespace detail
sl@0: {
sl@0:   namespace error
sl@0:   {
sl@0:     template <int keywords, int init_args>
sl@0:     struct more_keywords_than_init_arguments
sl@0:     {
sl@0:         typedef char too_many_keywords[init_args - keywords >= 0 ? 1 : -1];
sl@0:     };
sl@0:   }
sl@0: 
sl@0:   //  is_optional<T>::value
sl@0:   //
sl@0:   //      This metaprogram checks if T is an optional
sl@0:   //
sl@0: #if defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
sl@0: 
sl@0:     template <class T>
sl@0:     struct is_optional {
sl@0: 
sl@0:     private:
sl@0: 
sl@0:         template <BOOST_PYTHON_OVERLOAD_TYPES>
sl@0:         static boost::type_traits::yes_type f(optional<BOOST_PYTHON_OVERLOAD_ARGS>);
sl@0:         static boost::type_traits::no_type f(...);
sl@0:         static T t();
sl@0: 
sl@0:     public:
sl@0: 
sl@0:         BOOST_STATIC_CONSTANT(
sl@0:             bool, value =
sl@0:                 sizeof(f(t())) == sizeof(::boost::type_traits::yes_type));
sl@0:         typedef mpl::bool_<value> type;
sl@0:     };
sl@0: 
sl@0: #else
sl@0: 
sl@0:     template <class T>
sl@0:     struct is_optional
sl@0:       : mpl::false_
sl@0:     {};
sl@0: 
sl@0:     template <BOOST_PYTHON_OVERLOAD_TYPES>
sl@0:     struct is_optional<optional<BOOST_PYTHON_OVERLOAD_ARGS> >
sl@0:       : mpl::true_
sl@0:     {};
sl@0:   
sl@0: #endif
sl@0: 
sl@0:   template <int NDefaults>
sl@0:   struct define_class_init_helper;
sl@0: 
sl@0: } // namespace detail
sl@0: 
sl@0: template <class DerivedT>
sl@0: struct init_base : def_visitor<DerivedT>
sl@0: {
sl@0:     init_base(char const* doc_, detail::keyword_range const& keywords_)
sl@0:         : m_doc(doc_), m_keywords(keywords_)
sl@0:     {}
sl@0:         
sl@0:     init_base(char const* doc_)
sl@0:         : m_doc(doc_)
sl@0:     {}
sl@0: 
sl@0:     DerivedT const& derived() const
sl@0:     {
sl@0:         return *static_cast<DerivedT const*>(this);
sl@0:     }
sl@0:     
sl@0:     char const* doc_string() const
sl@0:     {
sl@0:         return m_doc;
sl@0:     }
sl@0: 
sl@0:     detail::keyword_range const& keywords() const
sl@0:     {
sl@0:         return m_keywords;
sl@0:     }
sl@0: 
sl@0:     static default_call_policies call_policies()
sl@0:     {
sl@0:         return default_call_policies();
sl@0:     }
sl@0: 
sl@0:  private:
sl@0:     //  visit
sl@0:     //
sl@0:     //      Defines a set of n_defaults + 1 constructors for its
sl@0:     //      class_<...> argument. Each constructor after the first has
sl@0:     //      one less argument to its right. Example:
sl@0:     //
sl@0:     //          init<int, optional<char, long, double> >
sl@0:     //
sl@0:     //      Defines:
sl@0:     //
sl@0:     //          __init__(int, char, long, double)
sl@0:     //          __init__(int, char, long)
sl@0:     //          __init__(int, char)
sl@0:     //          __init__(int)
sl@0:     template <class classT>
sl@0:     void visit(classT& cl) const
sl@0:     {
sl@0:         typedef typename DerivedT::signature signature;
sl@0:         typedef typename DerivedT::n_arguments n_arguments;
sl@0:         typedef typename DerivedT::n_defaults n_defaults;
sl@0:     
sl@0:         detail::define_class_init_helper<n_defaults::value>::apply(
sl@0:             cl
sl@0:           , derived().call_policies()
sl@0:           , signature()
sl@0:           , n_arguments()
sl@0:           , derived().doc_string()
sl@0:           , derived().keywords());
sl@0:     }
sl@0:     
sl@0:     friend class python::def_visitor_access;
sl@0:     
sl@0:  private: // data members
sl@0:     char const* m_doc;
sl@0:     detail::keyword_range m_keywords;
sl@0: };
sl@0: 
sl@0: template <class CallPoliciesT, class InitT>
sl@0: class init_with_call_policies
sl@0:     : public init_base<init_with_call_policies<CallPoliciesT, InitT> >
sl@0: {
sl@0:     typedef init_base<init_with_call_policies<CallPoliciesT, InitT> > base;
sl@0:  public:
sl@0:     typedef typename InitT::n_arguments n_arguments;
sl@0:     typedef typename InitT::n_defaults n_defaults;
sl@0:     typedef typename InitT::signature signature;
sl@0: 
sl@0:     init_with_call_policies(
sl@0:         CallPoliciesT const& policies_
sl@0:         , char const* doc_
sl@0:         , detail::keyword_range const& keywords
sl@0:         )
sl@0:         : base(doc_, keywords)
sl@0:         , m_policies(policies_)
sl@0:     {}
sl@0: 
sl@0:     CallPoliciesT const& call_policies() const
sl@0:     {
sl@0:         return this->m_policies;
sl@0:     }
sl@0:     
sl@0:  private: // data members
sl@0:     CallPoliciesT m_policies;
sl@0: };
sl@0: 
sl@0: //
sl@0: // drop1<S> is the initial length(S) elements of S
sl@0: //
sl@0: namespace detail
sl@0: {
sl@0:   template <class S>
sl@0:   struct drop1
sl@0:     : mpl::iterator_range<
sl@0:           typename mpl::begin<S>::type
sl@0:         , typename mpl::prior<
sl@0:               typename mpl::end<S>::type
sl@0:           >::type
sl@0:       >
sl@0:   {};
sl@0: }
sl@0: 
sl@0: template <BOOST_PYTHON_OVERLOAD_TYPES>
sl@0: class init : public init_base<init<BOOST_PYTHON_OVERLOAD_ARGS> >
sl@0: {
sl@0:     typedef init_base<init<BOOST_PYTHON_OVERLOAD_ARGS> > base;
sl@0:  public:
sl@0:     typedef init<BOOST_PYTHON_OVERLOAD_ARGS> self_t;
sl@0: 
sl@0:     init(char const* doc_ = 0)
sl@0:         : base(doc_)
sl@0:     {
sl@0:     }
sl@0: 
sl@0:     template <std::size_t N>
sl@0:     init(char const* doc_, detail::keywords<N> const& kw)
sl@0:         : base(doc_, kw.range())
sl@0:     {
sl@0:         typedef typename detail::error::more_keywords_than_init_arguments<
sl@0:             N, n_arguments::value
sl@0:             >::too_many_keywords assertion;
sl@0:     }
sl@0: 
sl@0:     template <std::size_t N>
sl@0:     init(detail::keywords<N> const& kw, char const* doc_ = 0)
sl@0:         : base(doc_, kw.range())
sl@0:     {
sl@0:         typedef typename detail::error::more_keywords_than_init_arguments<
sl@0:             N, n_arguments::value
sl@0:             >::too_many_keywords assertion;
sl@0:     }
sl@0: 
sl@0:     template <class CallPoliciesT>
sl@0:     init_with_call_policies<CallPoliciesT, self_t>
sl@0:     operator[](CallPoliciesT const& policies) const
sl@0:     {
sl@0:         return init_with_call_policies<CallPoliciesT, self_t>(
sl@0:             policies, this->doc_string(), this->keywords());
sl@0:     }
sl@0: 
sl@0:     typedef detail::type_list<BOOST_PYTHON_OVERLOAD_ARGS> signature_;
sl@0: 
sl@0:     typedef detail::is_optional<
sl@0:         typename mpl::eval_if<
sl@0:             mpl::empty<signature_>
sl@0:           , mpl::false_
sl@0:           , mpl::back<signature_>
sl@0:         >::type
sl@0:     > back_is_optional;
sl@0:     
sl@0:     typedef typename mpl::eval_if<
sl@0:         back_is_optional
sl@0:       , mpl::back<signature_>
sl@0:       , mpl::vector0<>
sl@0:     >::type optional_args;
sl@0: 
sl@0:     typedef typename mpl::eval_if<
sl@0:         back_is_optional
sl@0:       , mpl::if_<
sl@0:             mpl::empty<optional_args>
sl@0:           , detail::drop1<signature_>
sl@0:           , mpl::joint_view<
sl@0:                 detail::drop1<signature_>
sl@0:               , optional_args
sl@0:             >
sl@0:         >
sl@0:       , signature_
sl@0:     >::type signature;
sl@0: 
sl@0:     // TODO: static assert to make sure there are no other optional elements
sl@0: 
sl@0:     // Count the number of default args
sl@0:     typedef mpl::size<optional_args> n_defaults;
sl@0:     typedef mpl::size<signature> n_arguments;
sl@0: };
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: //
sl@0: //  optional
sl@0: //
sl@0: //      optional<T0...TN>::type returns a typelist.
sl@0: //
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: template <BOOST_PYTHON_OVERLOAD_TYPES>
sl@0: struct optional
sl@0:     : detail::type_list<BOOST_PYTHON_OVERLOAD_ARGS>
sl@0: {
sl@0: };
sl@0: 
sl@0: namespace detail
sl@0: {
sl@0:   template <class ClassT, class CallPoliciesT, class Signature, class NArgs>
sl@0:   inline void def_init_aux(
sl@0:       ClassT& cl
sl@0:       , Signature const&
sl@0:       , NArgs
sl@0:       , CallPoliciesT const& policies
sl@0:       , char const* doc
sl@0:       , detail::keyword_range const& keywords_
sl@0:       )
sl@0:   {
sl@0:       cl.def(
sl@0:           "__init__"
sl@0:         , detail::make_keyword_range_constructor<Signature,NArgs>(
sl@0:               policies
sl@0:             , keywords_
sl@0:             , (typename ClassT::metadata::holder*)0
sl@0:           )
sl@0:         , doc
sl@0:       );
sl@0:   }
sl@0: 
sl@0:   ///////////////////////////////////////////////////////////////////////////////
sl@0:   //
sl@0:   //  define_class_init_helper<N>::apply
sl@0:   //
sl@0:   //      General case
sl@0:   //
sl@0:   //      Accepts a class_ and an arguments list. Defines a constructor
sl@0:   //      for the class given the arguments and recursively calls
sl@0:   //      define_class_init_helper<N-1>::apply with one fewer argument (the
sl@0:   //      rightmost argument is shaved off)
sl@0:   //
sl@0:   ///////////////////////////////////////////////////////////////////////////////
sl@0:   template <int NDefaults>
sl@0:   struct define_class_init_helper
sl@0:   {
sl@0: 
sl@0:       template <class ClassT, class CallPoliciesT, class Signature, class NArgs>
sl@0:       static void apply(
sl@0:           ClassT& cl
sl@0:           , CallPoliciesT const& policies
sl@0:           , Signature const& args
sl@0:           , NArgs
sl@0:           , char const* doc
sl@0:           , detail::keyword_range keywords)
sl@0:       {
sl@0:           detail::def_init_aux(cl, args, NArgs(), policies, 0, keywords);
sl@0: 
sl@0:           if (keywords.second > keywords.first)
sl@0:               --keywords.second;
sl@0: 
sl@0:           typedef typename mpl::prior<NArgs>::type next_nargs;
sl@0:           define_class_init_helper<NDefaults-1>::apply(
sl@0:               cl, policies, Signature(), next_nargs(), doc, keywords);
sl@0:       }
sl@0:   };
sl@0: 
sl@0:   ///////////////////////////////////////////////////////////////////////////////
sl@0:   //
sl@0:   //  define_class_init_helper<0>::apply
sl@0:   //
sl@0:   //      Terminal case
sl@0:   //
sl@0:   //      Accepts a class_ and an arguments list. Defines a constructor
sl@0:   //      for the class given the arguments.
sl@0:   //
sl@0:   ///////////////////////////////////////////////////////////////////////////////
sl@0:   template <>
sl@0:   struct define_class_init_helper<0> {
sl@0: 
sl@0:       template <class ClassT, class CallPoliciesT, class Signature, class NArgs>
sl@0:       static void apply(
sl@0:           ClassT& cl
sl@0:         , CallPoliciesT const& policies
sl@0:         , Signature const& args
sl@0:         , NArgs
sl@0:         , char const* doc
sl@0:         , detail::keyword_range const& keywords)
sl@0:       {
sl@0:           detail::def_init_aux(cl, args, NArgs(), policies, doc, keywords);
sl@0:       }
sl@0:   };
sl@0: }
sl@0: 
sl@0: }} // namespace boost::python
sl@0: 
sl@0: #undef BOOST_PYTHON_OVERLOAD_TYPES_WITH_DEFAULT
sl@0: #undef BOOST_PYTHON_OVERLOAD_TYPES
sl@0: #undef BOOST_PYTHON_OVERLOAD_ARGS
sl@0: #undef BOOST_PYTHON_IS_OPTIONAL_VALUE
sl@0: #undef BOOST_PYTHON_APPEND_TO_INIT
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: #endif // INIT_JDG20020820_HPP
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: 
sl@0: