comparison DEPENDENCIES/generic/include/boost/proto/transform/call.hpp @ 16:2665513ce2d3

Add boost headers

+///////////////////////////////////////////////////////////////////////////////
+/// \file call.hpp
+/// Contains definition of the call<> transform.
+//
+//  Copyright 2008 Eric Niebler. 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 BOOST_PROTO_TRANSFORM_CALL_HPP_EAN_11_02_2007
+#define BOOST_PROTO_TRANSFORM_CALL_HPP_EAN_11_02_2007
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma warning(push)
+# pragma warning(disable: 4714) // function 'xxx' marked as __forceinline not inlined
+#endif
+
+#include <boost/preprocessor/cat.hpp>
+#include <boost/preprocessor/facilities/intercept.hpp>
+#include <boost/preprocessor/iteration/iterate.hpp>
+#include <boost/preprocessor/repetition/enum.hpp>
+#include <boost/preprocessor/repetition/repeat.hpp>
+#include <boost/preprocessor/repetition/enum_params.hpp>
+#include <boost/preprocessor/repetition/enum_binary_params.hpp>
+#include <boost/preprocessor/repetition/enum_trailing_params.hpp>
+#include <boost/ref.hpp>
+#include <boost/utility/result_of.hpp>
+#include <boost/proto/proto_fwd.hpp>
+#include <boost/proto/traits.hpp>
+#include <boost/proto/transform/impl.hpp>
+#include <boost/proto/detail/as_lvalue.hpp>
+#include <boost/proto/detail/poly_function.hpp>
+#include <boost/proto/transform/detail/pack.hpp>
+
+namespace boost { namespace proto
+{
+    /// \brief Wrap \c PrimitiveTransform so that <tt>when\<\></tt> knows
+    /// it is callable. Requires that the parameter is actually a
+    /// PrimitiveTransform.
+    ///
+    /// This form of <tt>call\<\></tt> is useful for annotating an
+    /// arbitrary PrimitiveTransform as callable when using it with
+    /// <tt>when\<\></tt>. Consider the following transform, which
+    /// is parameterized with another transform.
+    ///
+    /// \code
+    /// template<typename Grammar>
+    /// struct Foo
+    ///   : when<
+    ///         unary_plus<Grammar>
+    ///       , Grammar(_child)   // May or may not work.
+    ///     >
+    /// {};
+    /// \endcode
+    ///
+    /// The problem with the above is that <tt>when\<\></tt> may or
+    /// may not recognize \c Grammar as callable, depending on how
+    /// \c Grammar is implemented. (See <tt>is_callable\<\></tt> for
+    /// a discussion of this issue.) You can guard against
+    /// the issue by wrapping \c Grammar in <tt>call\<\></tt>, such
+    /// as:
+    ///
+    /// \code
+    /// template<typename Grammar>
+    /// struct Foo
+    ///   : when<
+    ///         unary_plus<Grammar>
+    ///       , call<Grammar>(_child)   // OK, this works
+    ///     >
+    /// {};
+    /// \endcode
+    ///
+    /// The above could also have been written as:
+    ///
+    /// \code
+    /// template<typename Grammar>
+    /// struct Foo
+    ///   : when<
+    ///         unary_plus<Grammar>
+    ///       , call<Grammar(_child)>   // OK, this works, too
+    ///     >
+    /// {};
+    /// \endcode
+    template<typename PrimitiveTransform>
+    struct call
+      : PrimitiveTransform
+    {};
+
+    /// \brief A specialization that treats function pointer Transforms as
+    /// if they were function type Transforms.
+    ///
+    /// This specialization requires that \c Fun is actually a function type.
+    ///
+    /// This specialization is required for nested transforms such as
+    /// <tt>call\<T0(T1(_))\></tt>. In C++, functions that are used as
+    /// parameters to other functions automatically decay to funtion
+    /// pointer types. In other words, the type <tt>T0(T1(_))</tt> is
+    /// indistinguishable from <tt>T0(T1(*)(_))</tt>. This specialization
+    /// is required to handle these nested function pointer type transforms
+    /// properly.
+    template<typename Fun>
+    struct call<Fun *>
+      : call<Fun>
+    {};
+
+    /// INTERNAL ONLY
+    template<typename Fun>
+    struct call<detail::msvc_fun_workaround<Fun> >
+      : call<Fun>
+    {};
+
+    /// \brief Either call the PolymorphicFunctionObject with 0
+    /// arguments, or invoke the PrimitiveTransform with 3
+    /// arguments.
+    template<typename Fun>
+    struct call<Fun()> : transform<call<Fun()> >
+    {
+        /// INTERNAL ONLY
+        template<typename Expr, typename State, typename Data, bool B>
+        struct impl2
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename BOOST_PROTO_RESULT_OF<Fun()>::type result_type;
+
+            BOOST_FORCEINLINE
+            result_type operator()(
+                typename impl2::expr_param
+              , typename impl2::state_param
+              , typename impl2::data_param
+            ) const
+            {
+                return Fun()();
+            }
+        };
+
+        /// INTERNAL ONLY
+        template<typename Expr, typename State, typename Data>
+        struct impl2<Expr, State, Data, true>
+          : Fun::template impl<Expr, State, Data>
+        {};
+
+        /// Either call the PolymorphicFunctionObject \c Fun with 0 arguments; or
+        /// invoke the PrimitiveTransform \c Fun with 3 arguments: the current
+        /// expression, state, and data.
+        ///
+        /// If \c Fun is a nullary PolymorphicFunctionObject, return <tt>Fun()()</tt>.
+        /// Otherwise, return <tt>Fun()(e, s, d)</tt>.
+        ///
+        /// \param e The current expression
+        /// \param s The current state
+        /// \param d An arbitrary data
+
+        /// If \c Fun is a nullary PolymorphicFunctionObject, \c type is a typedef
+        /// for <tt>boost::result_of\<Fun()\>::type</tt>. Otherwise, it is
+        /// a typedef for <tt>boost::result_of\<Fun(Expr, State, Data)\>::type</tt>.
+        template<typename Expr, typename State, typename Data>
+        struct impl
+          : impl2<Expr, State, Data, detail::is_transform_<Fun>::value>
+        {};
+    };
+
+    /// \brief Either call the PolymorphicFunctionObject with 1
+    /// argument, or invoke the PrimitiveTransform with 3
+    /// arguments.
+    template<typename Fun, typename A0>
+    struct call<Fun(A0)> : transform<call<Fun(A0)> >
+    {
+        template<typename Expr, typename State, typename Data, bool B>
+        struct impl2
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename when<_, A0>::template impl<Expr, State, Data>::result_type a0;
+            typedef typename detail::poly_function_traits<Fun, Fun(a0)>::result_type result_type;
+            
+            BOOST_FORCEINLINE
+            result_type operator ()(
+                typename impl2::expr_param   e
+              , typename impl2::state_param  s
+              , typename impl2::data_param   d
+            ) const
+            {
+                return typename detail::poly_function_traits<Fun, Fun(a0)>::function_type()(
+                    detail::as_lvalue(typename when<_, A0>::template impl<Expr, State, Data>()(e, s, d))
+                );
+            }
+        };
+
+        template<typename Expr, typename State, typename Data>
+        struct impl2<Expr, State, Data, true>
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename when<_, A0>::template impl<Expr, State, Data>::result_type a0;
+            typedef typename Fun::template impl<a0, State, Data>::result_type result_type;
+            
+            BOOST_FORCEINLINE
+            result_type operator ()(
+                typename impl2::expr_param   e
+              , typename impl2::state_param  s
+              , typename impl2::data_param   d
+            ) const
+            {
+                return typename Fun::template impl<a0, State, Data>()(
+                    typename when<_, A0>::template impl<Expr, State, Data>()(e, s, d)
+                  , s
+                  , d
+                );
+            }
+        };
+        /// Let \c x be <tt>when\<_, A0\>()(e, s, d)</tt> and \c X
+        /// be the type of \c x.
+        /// If \c Fun is a unary PolymorphicFunctionObject that accepts \c x,
+        /// then \c type is a typedef for <tt>boost::result_of\<Fun(X)\>::type</tt>.
+        /// Otherwise, it is a typedef for <tt>boost::result_of\<Fun(X, State, Data)\>::type</tt>.
+
+        /// Either call the PolymorphicFunctionObject with 1 argument:
+        /// the result of applying the \c A0 transform; or
+        /// invoke the PrimitiveTransform with 3 arguments:
+        /// result of applying the \c A0 transform, the state, and the
+        /// data.
+        ///
+        /// Let \c x be <tt>when\<_, A0\>()(e, s, d)</tt>.
+        /// If \c Fun is a unary PolymorphicFunctionObject that accepts \c x,
+        /// then return <tt>Fun()(x)</tt>. Otherwise, return
+        /// <tt>Fun()(x, s, d)</tt>.
+        ///
+        /// \param e The current expression
+        /// \param s The current state
+        /// \param d An arbitrary data
+        template<typename Expr, typename State, typename Data>
+        struct impl
+          : impl2<Expr, State, Data, detail::is_transform_<Fun>::value>
+        {};
+    };
+
+    /// \brief Either call the PolymorphicFunctionObject with 2
+    /// arguments, or invoke the PrimitiveTransform with 3
+    /// arguments.
+    template<typename Fun, typename A0, typename A1>
+    struct call<Fun(A0, A1)> : transform<call<Fun(A0, A1)> >
+    {
+        template<typename Expr, typename State, typename Data, bool B>
+        struct impl2
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename when<_, A0>::template impl<Expr, State, Data>::result_type a0;
+            typedef typename when<_, A1>::template impl<Expr, State, Data>::result_type a1;
+            typedef typename detail::poly_function_traits<Fun, Fun(a0, a1)>::result_type result_type;
+            
+            BOOST_FORCEINLINE
+            result_type operator ()(
+                typename impl2::expr_param   e
+              , typename impl2::state_param  s
+              , typename impl2::data_param   d
+            ) const
+            {
+                return typename detail::poly_function_traits<Fun, Fun(a0, a1)>::function_type()(
+                    detail::as_lvalue(typename when<_, A0>::template impl<Expr, State, Data>()(e, s, d))
+                  , detail::as_lvalue(typename when<_, A1>::template impl<Expr, State, Data>()(e, s, d))
+                );
+            }
+        };
+
+        template<typename Expr, typename State, typename Data>
+        struct impl2<Expr, State, Data, true>
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename when<_, A0>::template impl<Expr, State, Data>::result_type a0;
+            typedef typename when<_, A1>::template impl<Expr, State, Data>::result_type a1;
+            typedef typename Fun::template impl<a0, a1, Data>::result_type result_type;
+            
+            BOOST_FORCEINLINE
+            result_type operator ()(
+                typename impl2::expr_param   e
+              , typename impl2::state_param  s
+              , typename impl2::data_param   d
+            ) const
+            {
+                return typename Fun::template impl<a0, a1, Data>()(
+                    typename when<_, A0>::template impl<Expr, State, Data>()(e, s, d)
+                  , typename when<_, A1>::template impl<Expr, State, Data>()(e, s, d)
+                  , d
+                );
+            }
+        };
+
+            /// Let \c x be <tt>when\<_, A0\>()(e, s, d)</tt> and \c X
+            /// be the type of \c x.
+            /// Let \c y be <tt>when\<_, A1\>()(e, s, d)</tt> and \c Y
+            /// be the type of \c y.
+            /// If \c Fun is a binary PolymorphicFunction object that accepts \c x
+            /// and \c y, then \c type is a typedef for
+            /// <tt>boost::result_of\<Fun(X, Y)\>::type</tt>. Otherwise, it is
+            /// a typedef for <tt>boost::result_of\<Fun(X, Y, Data)\>::type</tt>.
+
+        /// Either call the PolymorphicFunctionObject with 2 arguments:
+        /// the result of applying the \c A0 transform, and the
+        /// result of applying the \c A1 transform; or invoke the
+        /// PrimitiveTransform with 3 arguments: the result of applying
+        /// the \c A0 transform, the result of applying the \c A1
+        /// transform, and the data.
+        ///
+        /// Let \c x be <tt>when\<_, A0\>()(e, s, d)</tt>.
+        /// Let \c y be <tt>when\<_, A1\>()(e, s, d)</tt>.
+        /// If \c Fun is a binary PolymorphicFunction object that accepts \c x
+        /// and \c y, return <tt>Fun()(x, y)</tt>. Otherwise, return
+        /// <tt>Fun()(x, y, d)</tt>.
+        ///
+        /// \param e The current expression
+        /// \param s The current state
+        /// \param d An arbitrary data
+        template<typename Expr, typename State, typename Data>
+        struct impl
+          : impl2<Expr, State, Data, detail::is_transform_<Fun>::value>
+        {};
+    };
+
+    /// \brief Call the PolymorphicFunctionObject or the
+    /// PrimitiveTransform with the current expression, state
+    /// and data, transformed according to \c A0, \c A1, and
+    /// \c A2, respectively.
+    template<typename Fun, typename A0, typename A1, typename A2>
+    struct call<Fun(A0, A1, A2)> : transform<call<Fun(A0, A1, A2)> >
+    {
+        template<typename Expr, typename State, typename Data, bool B>
+        struct impl2
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename when<_, A0>::template impl<Expr, State, Data>::result_type a0;
+            typedef typename when<_, A1>::template impl<Expr, State, Data>::result_type a1;
+            typedef typename when<_, A2>::template impl<Expr, State, Data>::result_type a2;
+            typedef typename detail::poly_function_traits<Fun, Fun(a0, a1, a2)>::result_type result_type;
+            
+            BOOST_FORCEINLINE
+            result_type operator ()(
+                typename impl2::expr_param   e
+              , typename impl2::state_param  s
+              , typename impl2::data_param   d
+            ) const
+            {
+                return typename detail::poly_function_traits<Fun, Fun(a0, a1, a2)>::function_type()(
+                    detail::as_lvalue(typename when<_, A0>::template impl<Expr, State, Data>()(e, s, d))
+                  , detail::as_lvalue(typename when<_, A1>::template impl<Expr, State, Data>()(e, s, d))
+                  , detail::as_lvalue(typename when<_, A2>::template impl<Expr, State, Data>()(e, s, d))
+                );
+            }
+        };
+
+        template<typename Expr, typename State, typename Data>
+        struct impl2<Expr, State, Data, true>
+          : transform_impl<Expr, State, Data>
+        {
+            typedef typename when<_, A0>::template impl<Expr, State, Data>::result_type a0;
+            typedef typename when<_, A1>::template impl<Expr, State, Data>::result_type a1;
+            typedef typename when<_, A2>::template impl<Expr, State, Data>::result_type a2;
+            typedef typename Fun::template impl<a0, a1, a2>::result_type result_type;
+            
+            BOOST_FORCEINLINE
+            result_type operator ()(
+                typename impl2::expr_param   e
+              , typename impl2::state_param  s
+              , typename impl2::data_param   d
+            ) const
+            {
+                return typename Fun::template impl<a0, a1, a2>()(
+                    typename when<_, A0>::template impl<Expr, State, Data>()(e, s, d)
+                  , typename when<_, A1>::template impl<Expr, State, Data>()(e, s, d)
+                  , typename when<_, A2>::template impl<Expr, State, Data>()(e, s, d)
+                );
+            }
+        };
+
+        /// Let \c x be <tt>when\<_, A0\>()(e, s, d)</tt>.
+        /// Let \c y be <tt>when\<_, A1\>()(e, s, d)</tt>.
+        /// Let \c z be <tt>when\<_, A2\>()(e, s, d)</tt>.
+        /// Return <tt>Fun()(x, y, z)</tt>.
+        ///
+        /// \param e The current expression
+        /// \param s The current state
+        /// \param d An arbitrary data
+
+        template<typename Expr, typename State, typename Data>
+        struct impl
+          : impl2<Expr, State, Data, detail::is_transform_<Fun>::value>
+        {};
+    };
+
+    #include <boost/proto/transform/detail/call.hpp>
+
+    /// INTERNAL ONLY
+    ///
+    template<typename Fun>
+    struct is_callable<call<Fun> >
+      : mpl::true_
+    {};
+
+}} // namespace boost::proto
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma warning(pop)
+#endif
+
+#endif