boost/python/detail/defaults_gen.hpp
/////////////////////////////////////////////////////////////////////////////// // // Copyright David Abrahams 2002, Joel de Guzman, 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 DEFAULTS_GEN_JDG20020807_HPP #define DEFAULTS_GEN_JDG20020807_HPP #include <boost/python/detail/preprocessor.hpp> #include <boost/preprocessor/repeat.hpp> #include <boost/preprocessor/repeat_from_to.hpp> #include <boost/preprocessor/enum.hpp> #include <boost/preprocessor/enum_params.hpp> #include <boost/preprocessor/repetition/enum_binary_params.hpp> #include <boost/preprocessor/tuple.hpp> #include <boost/preprocessor/cat.hpp> #include <boost/preprocessor/arithmetic/sub.hpp> #include <boost/preprocessor/stringize.hpp> #include <boost/preprocessor/inc.hpp> #include <boost/preprocessor/empty.hpp> #include <boost/preprocessor/comma_if.hpp> #include <boost/config.hpp> #include <boost/mpl/begin_end.hpp> #include <boost/mpl/next.hpp> #include <boost/mpl/deref.hpp> #include <cstddef> namespace boost { namespace python { namespace detail { // overloads_base is used as a base class for all function // stubs. This class holds the doc_string of the stubs. struct overloads_base { overloads_base(char const* doc_) : m_doc(doc_) {} overloads_base(char const* doc_, detail::keyword_range const& kw) : m_doc(doc_), m_keywords(kw) {} char const* doc_string() const { return m_doc; } detail::keyword_range const& keywords() const { return m_keywords; } private: char const* m_doc; detail::keyword_range m_keywords; }; // overloads_proxy is generated by the overloads_common operator[] (see // below). This class holds a user defined call policies of the stubs. template <class CallPoliciesT, class OverloadsT> struct overloads_proxy : public overloads_base { typedef typename OverloadsT::non_void_return_type non_void_return_type; typedef typename OverloadsT::void_return_type void_return_type; overloads_proxy( CallPoliciesT const& policies_ , char const* doc , keyword_range const& kw ) : overloads_base(doc, kw) , policies(policies_) {} CallPoliciesT call_policies() const { return policies; } CallPoliciesT policies; }; // overloads_common is our default function stubs base class. This // class returns the default_call_policies in its call_policies() // member function. It can generate a overloads_proxy however through // its operator[] template <class DerivedT> struct overloads_common : public overloads_base { overloads_common(char const* doc) : overloads_base(doc) {} overloads_common(char const* doc, keyword_range const& kw) : overloads_base(doc, kw) {} default_call_policies call_policies() const { return default_call_policies(); } template <class CallPoliciesT> overloads_proxy<CallPoliciesT, DerivedT> operator[](CallPoliciesT const& policies) const { return overloads_proxy<CallPoliciesT, DerivedT>( policies, this->doc_string(), this->keywords()); } }; }}} // namespace boost::python::detail #define BOOST_PYTHON_TYPEDEF_GEN(z, index, data) \ typedef typename ::boost::mpl::next<BOOST_PP_CAT(iter, index)>::type \ BOOST_PP_CAT(iter, BOOST_PP_INC(index)); \ typedef typename ::boost::mpl::deref<BOOST_PP_CAT(iter, index)>::type \ BOOST_PP_CAT(T, index); #define BOOST_PYTHON_FUNC_WRAPPER_GEN(z, index, data) \ static RT BOOST_PP_CAT(func_, \ BOOST_PP_SUB_D(1, index, BOOST_PP_TUPLE_ELEM(3, 1, data))) ( \ BOOST_PP_ENUM_BINARY_PARAMS_Z( \ 1, index, T, arg)) \ { \ BOOST_PP_TUPLE_ELEM(3, 2, data) \ BOOST_PP_TUPLE_ELEM(3, 0, data)( \ BOOST_PP_ENUM_PARAMS( \ index, \ arg)); \ } #define BOOST_PYTHON_GEN_FUNCTION(fname, fstubs_name, n_args, n_dflts, ret) \ struct fstubs_name \ { \ BOOST_STATIC_CONSTANT(int, n_funcs = BOOST_PP_INC(n_dflts)); \ BOOST_STATIC_CONSTANT(int, max_args = n_funcs); \ \ template <typename SigT> \ struct gen \ { \ typedef typename ::boost::mpl::begin<SigT>::type rt_iter; \ typedef typename ::boost::mpl::deref<rt_iter>::type RT; \ typedef typename ::boost::mpl::next<rt_iter>::type iter0; \ \ BOOST_PP_REPEAT_2ND( \ n_args, \ BOOST_PYTHON_TYPEDEF_GEN, \ 0) \ \ BOOST_PP_REPEAT_FROM_TO_2( \ BOOST_PP_SUB_D(1, n_args, n_dflts), \ BOOST_PP_INC(n_args), \ BOOST_PYTHON_FUNC_WRAPPER_GEN, \ (fname, BOOST_PP_SUB_D(1, n_args, n_dflts), ret)) \ }; \ }; \ /////////////////////////////////////////////////////////////////////////////// #define BOOST_PYTHON_MEM_FUNC_WRAPPER_GEN(z, index, data) \ static RT BOOST_PP_CAT(func_, \ BOOST_PP_SUB_D(1, index, BOOST_PP_TUPLE_ELEM(3, 1, data))) ( \ ClassT obj BOOST_PP_COMMA_IF(index) \ BOOST_PP_ENUM_BINARY_PARAMS_Z(1, index, T, arg) \ ) \ { \ BOOST_PP_TUPLE_ELEM(3, 2, data) obj.BOOST_PP_TUPLE_ELEM(3, 0, data)( \ BOOST_PP_ENUM_PARAMS(index, arg) \ ); \ } #define BOOST_PYTHON_GEN_MEM_FUNCTION(fname, fstubs_name, n_args, n_dflts, ret) \ struct fstubs_name \ { \ BOOST_STATIC_CONSTANT(int, n_funcs = BOOST_PP_INC(n_dflts)); \ BOOST_STATIC_CONSTANT(int, max_args = n_funcs + 1); \ \ template <typename SigT> \ struct gen \ { \ typedef typename ::boost::mpl::begin<SigT>::type rt_iter; \ typedef typename ::boost::mpl::deref<rt_iter>::type RT; \ \ typedef typename ::boost::mpl::next<rt_iter>::type class_iter; \ typedef typename ::boost::mpl::deref<class_iter>::type ClassT; \ typedef typename ::boost::mpl::next<class_iter>::type iter0; \ \ BOOST_PP_REPEAT_2ND( \ n_args, \ BOOST_PYTHON_TYPEDEF_GEN, \ 0) \ \ BOOST_PP_REPEAT_FROM_TO_2( \ BOOST_PP_SUB_D(1, n_args, n_dflts), \ BOOST_PP_INC(n_args), \ BOOST_PYTHON_MEM_FUNC_WRAPPER_GEN, \ (fname, BOOST_PP_SUB_D(1, n_args, n_dflts), ret)) \ }; \ }; #define BOOST_PYTHON_OVERLOAD_CONSTRUCTORS(fstubs_name, n_args, n_dflts) \ fstubs_name(char const* doc = 0) \ : ::boost::python::detail::overloads_common<fstubs_name>(doc) {} \ template <std::size_t N> \ fstubs_name(char const* doc, ::boost::python::detail::keywords<N> const& keywords) \ : ::boost::python::detail::overloads_common<fstubs_name>( \ doc, keywords.range()) \ { \ typedef typename ::boost::python::detail:: \ error::more_keywords_than_function_arguments< \ N,n_args>::too_many_keywords assertion; \ } \ template <std::size_t N> \ fstubs_name(::boost::python::detail::keywords<N> const& keywords, char const* doc = 0) \ : ::boost::python::detail::overloads_common<fstubs_name>( \ doc, keywords.range()) \ { \ typedef typename ::boost::python::detail:: \ error::more_keywords_than_function_arguments< \ N,n_args>::too_many_keywords assertion; \ } # if defined(BOOST_NO_VOID_RETURNS) # define BOOST_PYTHON_GEN_FUNCTION_STUB(fname, fstubs_name, n_args, n_dflts) \ struct fstubs_name \ : public ::boost::python::detail::overloads_common<fstubs_name> \ { \ BOOST_PYTHON_GEN_FUNCTION( \ fname, non_void_return_type, n_args, n_dflts, return) \ BOOST_PYTHON_GEN_FUNCTION( \ fname, void_return_type, n_args, n_dflts, ;) \ \ BOOST_PYTHON_OVERLOAD_CONSTRUCTORS(fstubs_name, n_args, n_dflts) \ }; # define BOOST_PYTHON_GEN_MEM_FUNCTION_STUB(fname, fstubs_name, n_args, n_dflts) \ struct fstubs_name \ : public ::boost::python::detail::overloads_common<fstubs_name> \ { \ BOOST_PYTHON_GEN_MEM_FUNCTION( \ fname, non_void_return_type, n_args, n_dflts, return) \ BOOST_PYTHON_GEN_MEM_FUNCTION( \ fname, void_return_type, n_args, n_dflts, ;) \ \ BOOST_PYTHON_OVERLOAD_CONSTRUCTORS(fstubs_name, n_args + 1, n_dflts) \ }; # else // !defined(BOOST_NO_VOID_RETURNS) # define BOOST_PYTHON_GEN_FUNCTION_STUB(fname, fstubs_name, n_args, n_dflts) \ struct fstubs_name \ : public ::boost::python::detail::overloads_common<fstubs_name> \ { \ BOOST_PYTHON_GEN_FUNCTION( \ fname, non_void_return_type, n_args, n_dflts, return) \ \ typedef non_void_return_type void_return_type; \ BOOST_PYTHON_OVERLOAD_CONSTRUCTORS(fstubs_name, n_args, n_dflts) \ }; # define BOOST_PYTHON_GEN_MEM_FUNCTION_STUB(fname, fstubs_name, n_args, n_dflts) \ struct fstubs_name \ : public ::boost::python::detail::overloads_common<fstubs_name> \ { \ BOOST_PYTHON_GEN_MEM_FUNCTION( \ fname, non_void_return_type, n_args, n_dflts, return) \ \ typedef non_void_return_type void_return_type; \ BOOST_PYTHON_OVERLOAD_CONSTRUCTORS(fstubs_name, n_args + 1, n_dflts) \ }; # endif // !defined(BOOST_NO_VOID_RETURNS) /////////////////////////////////////////////////////////////////////////////// // // MAIN MACROS // // Given generator_name, fname, min_args and max_args, These macros // generate function stubs that forward to a function or member function // named fname. max_args is the arity of the function or member function // fname. fname can have default arguments. min_args is the minimum // arity that fname can accept. // // There are two versions: // // 1. BOOST_PYTHON_FUNCTION_OVERLOADS for free functions // 2. BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS for member functions. // // For instance, given a function: // // int // foo(int a, char b = 1, unsigned c = 2, double d = 3) // { // return a + b + c + int(d); // } // // The macro invocation: // // BOOST_PYTHON_FUNCTION_OVERLOADS(foo_stubs, foo, 1, 4) // // Generates this code: // // struct foo_stubsNonVoid // { // static const int n_funcs = 4; // static const int max_args = n_funcs; // // template <typename SigT> // struct gen // { // typedef typename ::boost::mpl::begin<SigT>::type rt_iter; // typedef typename rt_iter::type RT; // typedef typename rt_iter::next iter0; // typedef typename iter0::type T0; // typedef typename iter0::next iter1; // typedef typename iter1::type T1; // typedef typename iter1::next iter2; // typedef typename iter2::type T2; // typedef typename iter2::next iter3; // typedef typename iter3::type T3; // typedef typename iter3::next iter4; // // static RT func_0(T0 arg0) // { return foo(arg0); } // // static RT func_1(T0 arg0, T1 arg1) // { return foo(arg0, arg1); } // // static RT func_2(T0 arg0, T1 arg1, T2 arg2) // { return foo(arg0, arg1, arg2); } // // static RT func_3(T0 arg0, T1 arg1, T2 arg2, T3 arg3) // { return foo(arg0, arg1, arg2, arg3); } // }; // }; // // struct foo_overloads // : public boost::python::detail::overloads_common<foo_overloads> // { // typedef foo_overloadsNonVoid non_void_return_type; // typedef foo_overloadsNonVoid void_return_type; // // foo_overloads(char const* doc = 0) // : boost::python::detail::overloads_common<foo_overloads>(doc) {} // }; // // The typedefs non_void_return_type and void_return_type are // used to handle compilers that do not support void returns. The // example above typedefs non_void_return_type and // void_return_type to foo_overloadsNonVoid. On compilers that do // not support void returns, there are two versions: // foo_overloadsNonVoid and foo_overloadsVoid. The "Void" // version is almost identical to the "NonVoid" version except // for the return type (void) and the lack of the return keyword. // // See the overloads_common above for a description of the // foo_overloads' base class. // /////////////////////////////////////////////////////////////////////////////// #define BOOST_PYTHON_FUNCTION_OVERLOADS(generator_name, fname, min_args, max_args) \ BOOST_PYTHON_GEN_FUNCTION_STUB( \ fname, \ generator_name, \ max_args, \ BOOST_PP_SUB_D(1, max_args, min_args)) #define BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(generator_name, fname, min_args, max_args) \ BOOST_PYTHON_GEN_MEM_FUNCTION_STUB( \ fname, \ generator_name, \ max_args, \ BOOST_PP_SUB_D(1, max_args, min_args)) // deprecated macro names (to be removed) #define BOOST_PYTHON_FUNCTION_GENERATOR BOOST_PYTHON_FUNCTION_OVERLOADS #define BOOST_PYTHON_MEM_FUN_GENERATOR BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS /////////////////////////////////////////////////////////////////////////////// #endif // DEFAULTS_GEN_JDG20020807_HPP