initial commit

[SVN r14738]

include/boost/python/detail/def_helper.hpp

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+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef DEF_HELPER_DWA200287_HPP
+# define DEF_HELPER_DWA200287_HPP
+
+# include <boost/type_traits/ice.hpp>
+# include <boost/type_traits/same_traits.hpp>
+# include <boost/python/detail/string_literal.hpp>
+
+namespace boost { namespace python { namespace detail { 
+
+//
+// def_helper<T> --
+//
+//      A helper for def() functions which determines how to interpret
+//      an argument of type T which could be either CallPolicies or a
+//      string literal representing a docstring.
+//
+//      Generates two static functions:
+//
+//        get_policy(x), where x is of type T, returns a policies
+//        object: either a reference to x or default_call_policies()
+//        if x is a string literal.
+//
+//        get_doc(x, s), where s convertible to char const*, returns x
+//        if x is a string literal, s otherwise.
+
+template <bool is_string = false>
+struct def_helper_impl
+{
+    template <class P>
+    static P const& get_policy(P const& x) { return x; }
+      
+    template <class P>
+    static char const* get_doc(P const&, char const* doc) { return doc; }
+};
+
+template <>
+struct def_helper_impl<true>
+{
+    static python::default_call_policies get_policy(char const*) { return default_call_policies(); }
+    static char const* get_doc(char const* doc, char const*) { return doc; }
+};
+  
+template <class T>
+struct def_helper
+    : def_helper_impl<
+    type_traits::ice_or<
+    is_string_literal<T const>::value
+    , is_same<T, char const*>::value
+    , is_same<T, char*>::value
+>::value
+>
+{};
+
+}}} // namespace boost::python::detail
+
+#endif // DEF_HELPER_DWA200287_HPP