1///////////////////////////////////////////////////////////////////////////////
2/// \file as_expr.hpp
3/// Contains definition of the as_expr\<\> and as_child\<\> helper class
4/// templates used to implement proto::domain's as_expr\<\> and as_child\<\>
5/// member templates.
6//
7// Copyright 2010 Eric Niebler. Distributed under the Boost
8// Software License, Version 1.0. (See accompanying file
9// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
10
11#ifndef BOOST_PROTO_DETAIL_AS_EXPR_HPP_EAN_06_09_2010
12#define BOOST_PROTO_DETAIL_AS_EXPR_HPP_EAN_06_09_2010
13
14#include <boost/config.hpp>
15#include <boost/detail/workaround.hpp>
16#include <boost/type_traits/remove_const.hpp>
17#include <boost/proto/proto_fwd.hpp>
18#include <boost/proto/args.hpp>
19
20#if defined(_MSC_VER)
21# pragma warning(push)
22# pragma warning(disable : 4714) // function 'xxx' marked as __forceinline not inlined
23#endif
24
25namespace boost { namespace proto { namespace detail
26{
27
28 ////////////////////////////////////////////////////////////////////////////////////////////////
29 template<typename Generator>
30 struct base_generator
31 {
32 typedef Generator type;
33 };
34
35 template<typename Generator>
36 struct base_generator<use_basic_expr<Generator> >
37 {
38 typedef Generator type;
39 };
40
41 ////////////////////////////////////////////////////////////////////////////////////////////////
42 template<typename T, typename Generator, bool WantsBasicExpr>
43 struct as_expr;
44
45 ////////////////////////////////////////////////////////////////////////////////////////////////
46 template<typename T, typename Generator>
47 struct as_expr<T, Generator, false>
48 {
49 typedef typename term_traits<T &>::value_type value_type;
50 typedef proto::expr<proto::tag::terminal, term<value_type>, 0> expr_type;
51 typedef typename Generator::template result<Generator(expr_type)>::type result_type;
52
53 BOOST_FORCEINLINE
54 result_type operator()(T &t) const
55 {
56 return Generator()(expr_type::make(t));
57 }
58 };
59
60 ////////////////////////////////////////////////////////////////////////////////////////////////
61 template<typename T, typename Generator>
62 struct as_expr<T, Generator, true>
63 {
64 typedef typename term_traits<T &>::value_type value_type;
65 typedef proto::basic_expr<proto::tag::terminal, term<value_type>, 0> expr_type;
66 typedef typename Generator::template result<Generator(expr_type)>::type result_type;
67
68 BOOST_FORCEINLINE
69 result_type operator()(T &t) const
70 {
71 return Generator()(expr_type::make(t));
72 }
73 };
74
75 ////////////////////////////////////////////////////////////////////////////////////////////////
76 template<typename T>
77 struct as_expr<T, proto::default_generator, false>
78 {
79 typedef typename term_traits<T &>::value_type value_type;
80 typedef proto::expr<proto::tag::terminal, term<value_type>, 0> result_type;
81
82 BOOST_FORCEINLINE
83 result_type operator()(T &t) const
84 {
85 return result_type::make(t);
86 }
87 };
88
89 ////////////////////////////////////////////////////////////////////////////////////////////////
90 template<typename T>
91 struct as_expr<T, proto::default_generator, true>
92 {
93 typedef typename term_traits<T &>::value_type value_type;
94 typedef proto::basic_expr<proto::tag::terminal, term<value_type>, 0> result_type;
95
96 BOOST_FORCEINLINE
97 result_type operator()(T &t) const
98 {
99 return result_type::make(t);
100 }
101 };
102
103 ////////////////////////////////////////////////////////////////////////////////////////////////
104 template<typename T, typename Generator, bool WantsBasicExpr>
105 struct as_child;
106
107 ////////////////////////////////////////////////////////////////////////////////////////////////
108 template<typename T, typename Generator>
109 struct as_child<T, Generator, false>
110 {
111 #if BOOST_WORKAROUND(BOOST_MSVC, == 1310)
112 typedef typename term_traits<T &>::reference reference;
113 #else
114 typedef T &reference;
115 #endif
116 typedef proto::expr<proto::tag::terminal, term<reference>, 0> expr_type;
117 typedef typename Generator::template result<Generator(expr_type)>::type result_type;
118
119 BOOST_FORCEINLINE
120 result_type operator()(T &t) const
121 {
122 return Generator()(expr_type::make(t));
123 }
124 };
125
126 ////////////////////////////////////////////////////////////////////////////////////////////////
127 template<typename T, typename Generator>
128 struct as_child<T, Generator, true>
129 {
130 #if BOOST_WORKAROUND(BOOST_MSVC, == 1310)
131 typedef typename term_traits<T &>::reference reference;
132 #else
133 typedef T &reference;
134 #endif
135 typedef proto::basic_expr<proto::tag::terminal, term<reference>, 0> expr_type;
136 typedef typename Generator::template result<Generator(expr_type)>::type result_type;
137
138 BOOST_FORCEINLINE
139 result_type operator()(T &t) const
140 {
141 return Generator()(expr_type::make(t));
142 }
143 };
144
145 ////////////////////////////////////////////////////////////////////////////////////////////////
146 template<typename T>
147 struct as_child<T, proto::default_generator, false>
148 {
149 #if BOOST_WORKAROUND(BOOST_MSVC, == 1310)
150 typedef typename term_traits<T &>::reference reference;
151 #else
152 typedef T &reference;
153 #endif
154 typedef proto::expr<proto::tag::terminal, term<reference>, 0> result_type;
155
156 BOOST_FORCEINLINE
157 result_type operator()(T &t) const
158 {
159 return result_type::make(t);
160 }
161 };
162
163 ////////////////////////////////////////////////////////////////////////////////////////////////
164 template<typename T>
165 struct as_child<T, proto::default_generator, true>
166 {
167 #if BOOST_WORKAROUND(BOOST_MSVC, == 1310)
168 typedef typename term_traits<T &>::reference reference;
169 #else
170 typedef T &reference;
171 #endif
172 typedef proto::basic_expr<proto::tag::terminal, term<reference>, 0> result_type;
173
174 BOOST_FORCEINLINE
175 result_type operator()(T &t) const
176 {
177 return result_type::make(t);
178 }
179 };
180
181}}}
182
183#if defined(_MSC_VER)
184# pragma warning(pop)
185#endif
186
187#endif
188