comparison DEPENDENCIES/generic/include/boost/spirit/home/support/action_dispatch.hpp @ 16:2665513ce2d3

Add boost headers

+/*=============================================================================
+    Copyright (c) 2001-2011 Joel de Guzman
+    Copyright (c) 2001-2011 Hartmut Kaiser
+    http://spirit.sourceforge.net/
+
+    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)
+=============================================================================*/
+#if !defined(BOOST_SPIRIT_ACTION_DISPATCH_APRIL_18_2008_0720AM)
+#define BOOST_SPIRIT_ACTION_DISPATCH_APRIL_18_2008_0720AM
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include<boost/config.hpp>
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && !defined(BOOST_NO_CXX11_LAMBDAS) && \
+    !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_DECLTYPE)
+#include <utility>
+#include <type_traits>
+#endif
+
+
+#include <boost/spirit/include/phoenix_core.hpp>
+#include <boost/spirit/home/support/attributes.hpp>
+
+namespace boost { namespace spirit { namespace traits
+{
+    template <typename Component>
+    struct action_dispatch
+    {
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && !defined(BOOST_NO_CXX11_LAMBDAS) && \
+    !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_DECLTYPE)
+        // omit function parameters without specializing for each possible
+        // type of callable entity
+        // many thanks to Eelis/##iso-c++ for this contribution
+
+    private:
+        // this will be used to pass around POD types which are safe
+        // to go through the ellipsis operator (if ever used)
+        template <typename>
+        struct fwd_tag {};
+
+        // the first parameter is a placeholder to obtain SFINAE when
+        // doing overload resolution, the second one is the actual
+        // forwarder, where we can apply our implementation
+        template <typename, typename T>
+        struct fwd_storage { typedef T type; };
+
+        // gcc should accept fake<T>() but it prints a sorry, needs
+        // a check once the bug is sorted out, use a FAKE_CALL macro for now
+        template <typename T>
+        T fake_call();
+
+#define BOOST_SPIRIT_FAKE_CALL(T) (*(T*)0)
+
+        // the forwarders, here we could tweak the implementation of
+        // how parameters are passed to the functions, if needed
+        struct fwd_none
+        {
+            template<typename F, typename... Rest>
+            auto operator()(F && f, Rest&&...) -> decltype(f())
+            {
+                return f();
+            }
+        };
+
+        struct fwd_attrib
+        {
+            template<typename F, typename A, typename... Rest>
+            auto operator()(F && f, A && a, Rest&&...) -> decltype(f(a))
+            {
+                 return f(a);
+            }
+        };
+
+        struct fwd_attrib_context
+        {
+             template<typename F, typename A, typename B, typename... Rest>
+             auto operator()(F && f, A && a, B && b, Rest&&...)
+                -> decltype(f(a, b))
+             {
+                 return f(a, b);
+             }
+        };
+
+        struct fwd_attrib_context_pass
+        {
+            template<typename F, typename A, typename B, typename C
+              , typename... Rest>
+            auto operator()(F && f, A && a, B && b, C && c, Rest&&...)
+               -> decltype(f(a, b, c))
+            {
+                return f(a, b, c);
+            }
+        };
+
+        // SFINAE for our calling syntax, the forwarders are stored based
+        // on what function call gives a proper result
+        // this code can probably be more generic once implementations are
+        // steady
+        template <typename F>
+        static auto do_call(F && f, ...)
+           -> typename fwd_storage<decltype(f()), fwd_none>::type
+        {
+            return {};
+        }
+
+        template <typename F, typename A>
+        static auto do_call(F && f, fwd_tag<A>, ...)
+           -> typename fwd_storage<decltype(f(BOOST_SPIRIT_FAKE_CALL(A)))
+                 , fwd_attrib>::type
+        {
+            return {};
+        }
+
+        template <typename F, typename A, typename B>
+        static auto do_call(F && f, fwd_tag<A>, fwd_tag<B>, ...)
+           -> typename fwd_storage<
+                    decltype(f(BOOST_SPIRIT_FAKE_CALL(A), BOOST_SPIRIT_FAKE_CALL(B)))
+                , fwd_attrib_context>::type
+        {
+            return {};
+        }
+
+        template <typename F, typename A, typename B, typename C>
+        static auto do_call(F && f, fwd_tag<A>, fwd_tag<B>, fwd_tag<C>, ...)
+           -> typename fwd_storage<
+                  decltype(f(BOOST_SPIRIT_FAKE_CALL(A), BOOST_SPIRIT_FAKE_CALL(B)
+                    , BOOST_SPIRIT_FAKE_CALL(C)))
+                , fwd_attrib_context_pass>::type
+        {
+            return {};
+        }
+
+        // this function calls the forwarder and is responsible for
+        // stripping the tail of the parameters
+        template <typename F, typename... A>
+        static void caller(F && f, A && ... a)
+        {
+            do_call(f, fwd_tag<typename std::remove_reference<A>::type>()...)
+                (std::forward<F>(f), std::forward<A>(a)...);
+        }
+
+#undef BOOST_SPIRIT_FAKE_CALL
+
+    public:
+        template <typename F, typename Attribute, typename Context>
+        bool operator()(F const& f, Attribute& attr, Context& context)
+        {
+            bool pass = true;
+            caller(f, attr, context, pass);
+            return pass;
+        }
+#else
+        // general handler for everything not explicitly specialized below
+        template <typename F, typename Attribute, typename Context>
+        bool operator()(F const& f, Attribute& attr, Context& context)
+        {
+            bool pass = true;
+            f(attr, context, pass);
+            return pass;
+        }
+#endif
+
+        // handler for phoenix actors
+
+        // If the component this action has to be invoked for is a tuple, we
+        // wrap any non-fusion tuple into a fusion tuple (done by pass_attribute)
+        // and pass through any fusion tuple.
+        template <typename Eval, typename Attribute, typename Context>
+        bool operator()(phoenix::actor<Eval> const& f
+          , Attribute& attr, Context& context)
+        {
+            bool pass = true;
+            typename pass_attribute<Component, Attribute>::type attr_wrap(attr);
+            f(attr_wrap, context, pass);
+            return pass;
+        }
+
+        // specializations for plain function pointers taking different number of
+        // arguments
+        template <typename RT, typename A0, typename A1, typename A2
+          , typename Attribute, typename Context>
+        bool operator()(RT(*f)(A0, A1, A2), Attribute& attr, Context& context)
+        {
+            bool pass = true;
+            f(attr, context, pass);
+            return pass;
+        }
+
+        template <typename RT, typename A0, typename A1
+          , typename Attribute, typename Context>
+        bool operator()(RT(*f)(A0, A1), Attribute& attr, Context& context)
+        {
+            f(attr, context);
+            return true;
+        }
+
+        template <typename RT, typename A0, typename Attribute, typename Context>
+        bool operator()(RT(*f)(A0), Attribute& attr, Context&)
+        {
+            f(attr);
+            return true;
+        }
+
+        template <typename RT, typename Attribute, typename Context>
+        bool operator()(RT(*f)(), Attribute&, Context&)
+        {
+            f();
+            return true;
+        }
+    };
+}}}
+
+#endif