| 1 | /*============================================================================= |
| 2 | Copyright (c) 2001-2011 Joel de Guzman |
| 3 | http://spirit.sourceforge.net/ |
| 4 | |
| 5 | Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 6 | file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| 7 | =============================================================================*/ |
| 8 | #ifndef BOOST_SPIRIT_META_COMPILER_OCTOBER_16_2008_1258PM |
| 9 | #define BOOST_SPIRIT_META_COMPILER_OCTOBER_16_2008_1258PM |
| 10 | |
| 11 | #if defined(_MSC_VER) |
| 12 | #pragma once |
| 13 | #endif |
| 14 | |
| 15 | #include <boost/config.hpp> |
| 16 | #include <boost/spirit/include/phoenix_limits.hpp> |
| 17 | #include <boost/detail/workaround.hpp> |
| 18 | #include <boost/spirit/include/phoenix_limits.hpp> // needs to be included before proto |
| 19 | #include <boost/proto/proto.hpp> |
| 20 | #include <boost/spirit/home/support/make_component.hpp> |
| 21 | #include <boost/spirit/home/support/modify.hpp> |
| 22 | #include <boost/spirit/home/support/detail/make_cons.hpp> |
| 23 | #include <boost/spirit/home/support/unused.hpp> |
| 24 | #include <boost/spirit/home/support/assert_msg.hpp> |
| 25 | #include <boost/utility/enable_if.hpp> |
| 26 | #include <boost/type_traits/remove_reference.hpp> |
| 27 | |
| 28 | namespace boost { namespace spirit |
| 29 | { |
| 30 | // Some defaults... |
| 31 | |
| 32 | template <typename Domain, typename Tag, typename Enable = void> |
| 33 | struct use_operator : mpl::false_ {}; |
| 34 | |
| 35 | template <typename Domain, typename T, typename Enable = void> |
| 36 | struct use_function : mpl::false_ {}; |
| 37 | |
| 38 | template <typename Domain, typename T, typename Enable = void> |
| 39 | struct use_directive : mpl::false_ {}; |
| 40 | |
| 41 | template <typename Domain, typename T, typename Enable /* = void */> |
| 42 | struct is_modifier_directive : mpl::false_ {}; |
| 43 | |
| 44 | template <typename Domain, typename T, typename Enable = void> |
| 45 | struct use_terminal : mpl::false_ {}; |
| 46 | |
| 47 | template <typename Domain, typename T, typename Enable /*= void*/> |
| 48 | struct flatten_tree : mpl::false_ {}; |
| 49 | |
| 50 | // Our meta-compiler. This is the main engine that hooks Spirit |
| 51 | // to the proto expression template engine. |
| 52 | |
| 53 | template <typename Domain> |
| 54 | struct meta_compiler |
| 55 | { |
| 56 | struct meta_grammar; |
| 57 | |
| 58 | BOOST_SPIRIT_ASSERT_MSG(( |
| 59 | !use_operator<Domain, proto::tag::subscript>::value |
| 60 | ), error_proto_tag_subscript_cannot_be_used, ()); |
| 61 | |
| 62 | #if !BOOST_WORKAROUND(BOOST_MSVC, < 1400) |
| 63 | // this is the non-broken part for compilers properly supporting |
| 64 | // partial template specialization (VC7.1 does not) |
| 65 | struct cases |
| 66 | { |
| 67 | template <typename Tag, typename Enable = void> |
| 68 | struct case_ |
| 69 | : proto::not_<proto::_> |
| 70 | {}; |
| 71 | |
| 72 | /////////////////////////////////////////////////////////////////// |
| 73 | // terminals |
| 74 | /////////////////////////////////////////////////////////////////// |
| 75 | template <typename Enable> |
| 76 | struct case_<proto::tag::terminal, Enable> |
| 77 | : proto::when< |
| 78 | proto::if_<use_terminal<Domain, proto::_value>()>, |
| 79 | detail::make_terminal<Domain> |
| 80 | > |
| 81 | {}; |
| 82 | |
| 83 | template <typename Tag> |
| 84 | struct case_<Tag, typename enable_if<use_operator<Domain, Tag> >::type> |
| 85 | : proto::or_< |
| 86 | /////////////////////////////////////////////////////////////////// |
| 87 | // binary operators |
| 88 | /////////////////////////////////////////////////////////////////// |
| 89 | proto::when<proto::binary_expr<Tag, meta_grammar, meta_grammar>, |
| 90 | detail::make_binary<Domain, Tag, meta_grammar> |
| 91 | >, |
| 92 | /////////////////////////////////////////////////////////////////// |
| 93 | // unary operators |
| 94 | /////////////////////////////////////////////////////////////////// |
| 95 | proto::when<proto::unary_expr<Tag, meta_grammar>, |
| 96 | detail::make_unary<Domain, Tag, meta_grammar> |
| 97 | > |
| 98 | > |
| 99 | {}; |
| 100 | |
| 101 | template <typename Enable> |
| 102 | struct case_<proto::tag::subscript, Enable> |
| 103 | : proto::or_< |
| 104 | /////////////////////////////////////////////////////////////////// |
| 105 | // directives |
| 106 | /////////////////////////////////////////////////////////////////// |
| 107 | proto::when<proto::binary_expr<proto::tag::subscript |
| 108 | , proto::and_< |
| 109 | proto::terminal<proto::_> |
| 110 | , proto::if_<use_directive<Domain, proto::_value >()> > |
| 111 | , meta_grammar>, |
| 112 | detail::make_directive<Domain, meta_grammar> |
| 113 | >, |
| 114 | /////////////////////////////////////////////////////////////////// |
| 115 | // semantic actions |
| 116 | /////////////////////////////////////////////////////////////////// |
| 117 | proto::when<proto::binary_expr<proto::tag::subscript |
| 118 | , meta_grammar, proto::_>, |
| 119 | detail::make_action<Domain, meta_grammar> |
| 120 | > |
| 121 | > |
| 122 | {}; |
| 123 | }; |
| 124 | #else |
| 125 | // this part actually constitutes invalid C++ code, but it allows us to |
| 126 | // convince VC7.1 to do what we want |
| 127 | struct cases |
| 128 | { |
| 129 | template <typename Tag, typename Enable = void> |
| 130 | struct case_ |
| 131 | : proto::not_<proto::_> |
| 132 | {}; |
| 133 | |
| 134 | /////////////////////////////////////////////////////////////////// |
| 135 | // terminals |
| 136 | /////////////////////////////////////////////////////////////////// |
| 137 | template <> |
| 138 | struct case_<proto::tag::terminal> |
| 139 | : proto::when< |
| 140 | proto::if_<use_terminal<Domain, proto::_value>()>, |
| 141 | detail::make_terminal<Domain> |
| 142 | > |
| 143 | {}; |
| 144 | |
| 145 | template <typename Tag> |
| 146 | struct case_<Tag> |
| 147 | : proto::or_< |
| 148 | /////////////////////////////////////////////////////////////////// |
| 149 | // binary operators |
| 150 | /////////////////////////////////////////////////////////////////// |
| 151 | proto::when<proto::binary_expr< |
| 152 | typename enable_if<use_operator<Domain, Tag>, Tag>::type |
| 153 | , meta_grammar, meta_grammar> |
| 154 | , detail::make_binary<Domain, Tag, meta_grammar> |
| 155 | >, |
| 156 | /////////////////////////////////////////////////////////////////// |
| 157 | // unary operators |
| 158 | /////////////////////////////////////////////////////////////////// |
| 159 | proto::when<proto::unary_expr< |
| 160 | typename enable_if<use_operator<Domain, Tag>, Tag>::type |
| 161 | , meta_grammar> |
| 162 | , detail::make_unary<Domain, Tag, meta_grammar> |
| 163 | > |
| 164 | > |
| 165 | {}; |
| 166 | |
| 167 | template <> |
| 168 | struct case_<proto::tag::subscript> |
| 169 | : proto::or_< |
| 170 | /////////////////////////////////////////////////////////////////// |
| 171 | // directives |
| 172 | /////////////////////////////////////////////////////////////////// |
| 173 | proto::when<proto::binary_expr<proto::tag::subscript |
| 174 | , proto::and_< |
| 175 | proto::terminal<proto::_> |
| 176 | , proto::if_<use_directive<Domain, proto::_value >()> > |
| 177 | , meta_grammar>, |
| 178 | detail::make_directive<Domain, meta_grammar> |
| 179 | >, |
| 180 | /////////////////////////////////////////////////////////////////// |
| 181 | // semantic actions |
| 182 | /////////////////////////////////////////////////////////////////// |
| 183 | proto::when<proto::binary_expr<proto::tag::subscript |
| 184 | , meta_grammar, proto::_>, |
| 185 | detail::make_action<Domain, meta_grammar> |
| 186 | > |
| 187 | > |
| 188 | {}; |
| 189 | }; |
| 190 | #endif |
| 191 | |
| 192 | struct meta_grammar |
| 193 | : proto::switch_<cases> |
| 194 | {}; |
| 195 | }; |
| 196 | |
| 197 | namespace result_of |
| 198 | { |
| 199 | // Default case |
| 200 | template <typename Domain, typename Expr |
| 201 | , typename Modifiers = unused_type, typename Enable = void> |
| 202 | struct compile |
| 203 | { |
| 204 | typedef typename meta_compiler<Domain>::meta_grammar meta_grammar; |
| 205 | typedef typename meta_grammar:: |
| 206 | template result<meta_grammar(Expr, mpl::void_, Modifiers)>::type |
| 207 | type; |
| 208 | }; |
| 209 | |
| 210 | // If Expr is not a proto expression, make it a terminal |
| 211 | template <typename Domain, typename Expr, typename Modifiers> |
| 212 | struct compile<Domain, Expr, Modifiers, |
| 213 | typename disable_if<proto::is_expr<Expr> >::type> |
| 214 | : compile<Domain, typename proto::terminal<Expr>::type, Modifiers> {}; |
| 215 | } |
| 216 | |
| 217 | namespace traits |
| 218 | { |
| 219 | // Check if Expr matches the domain's grammar |
| 220 | template <typename Domain, typename Expr> |
| 221 | struct matches : |
| 222 | proto::matches< |
| 223 | typename proto::result_of::as_expr< |
| 224 | typename remove_reference<Expr>::type>::type, |
| 225 | typename meta_compiler<Domain>::meta_grammar |
| 226 | > |
| 227 | { |
| 228 | }; |
| 229 | } |
| 230 | |
| 231 | namespace detail |
| 232 | { |
| 233 | template <typename Domain> |
| 234 | struct compiler |
| 235 | { |
| 236 | // Default case |
| 237 | template <typename Expr, typename Modifiers> |
| 238 | static typename spirit::result_of::compile<Domain, Expr, Modifiers>::type |
| 239 | compile(Expr const& expr, Modifiers modifiers, mpl::true_) |
| 240 | { |
| 241 | typename meta_compiler<Domain>::meta_grammar compiler; |
| 242 | return compiler(expr, mpl::void_(), modifiers); |
| 243 | } |
| 244 | |
| 245 | // If Expr is not a proto expression, make it a terminal |
| 246 | template <typename Expr, typename Modifiers> |
| 247 | static typename spirit::result_of::compile<Domain, Expr, Modifiers>::type |
| 248 | compile(Expr const& expr, Modifiers modifiers, mpl::false_) |
| 249 | { |
| 250 | typename meta_compiler<Domain>::meta_grammar compiler; |
| 251 | typedef typename detail::as_meta_element<Expr>::type expr_; |
| 252 | typename proto::terminal<expr_>::type term = {expr}; |
| 253 | return compiler(term, mpl::void_(), modifiers); |
| 254 | } |
| 255 | }; |
| 256 | } |
| 257 | |
| 258 | template <typename Domain, typename Expr> |
| 259 | inline typename result_of::compile<Domain, Expr, unused_type>::type |
| 260 | compile(Expr const& expr) |
| 261 | { |
| 262 | typedef typename proto::is_expr<Expr>::type is_expr; |
| 263 | return detail::compiler<Domain>::compile(expr, unused, is_expr()); |
| 264 | } |
| 265 | |
| 266 | template <typename Domain, typename Expr, typename Modifiers> |
| 267 | inline typename result_of::compile<Domain, Expr, Modifiers>::type |
| 268 | compile(Expr const& expr, Modifiers modifiers) |
| 269 | { |
| 270 | typedef typename proto::is_expr<Expr>::type is_expr; |
| 271 | return detail::compiler<Domain>::compile(expr, modifiers, is_expr()); |
| 272 | } |
| 273 | |
| 274 | /////////////////////////////////////////////////////////////////////////// |
| 275 | template <typename Elements, template <typename Subject> class generator> |
| 276 | struct make_unary_composite |
| 277 | { |
| 278 | typedef typename |
| 279 | fusion::result_of::value_at_c<Elements, 0>::type |
| 280 | element_type; |
| 281 | typedef generator<element_type> result_type; |
| 282 | result_type operator()(Elements const& elements, unused_type) const |
| 283 | { |
| 284 | return result_type(fusion::at_c<0>(elements)); |
| 285 | } |
| 286 | }; |
| 287 | |
| 288 | template <typename Elements, template <typename Left, typename Right> class generator> |
| 289 | struct make_binary_composite |
| 290 | { |
| 291 | typedef typename |
| 292 | fusion::result_of::value_at_c<Elements, 0>::type |
| 293 | left_type; |
| 294 | typedef typename |
| 295 | fusion::result_of::value_at_c<Elements, 1>::type |
| 296 | right_type; |
| 297 | typedef generator<left_type, right_type> result_type; |
| 298 | |
| 299 | result_type operator()(Elements const& elements, unused_type) const |
| 300 | { |
| 301 | return result_type( |
| 302 | fusion::at_c<0>(elements) |
| 303 | , fusion::at_c<1>(elements) |
| 304 | ); |
| 305 | } |
| 306 | }; |
| 307 | |
| 308 | template <typename Elements, template <typename Elements_> class generator> |
| 309 | struct make_nary_composite |
| 310 | { |
| 311 | typedef generator<Elements> result_type; |
| 312 | result_type operator()(Elements const& elements, unused_type) const |
| 313 | { |
| 314 | return result_type(elements); |
| 315 | } |
| 316 | }; |
| 317 | |
| 318 | }} |
| 319 | |
| 320 | #endif |
| 321 | |