real.hpp 12 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342
  1. /*=============================================================================
  2. Copyright (c) 2001-2011 Joel de Guzman
  3. Copyright (c) 2011 Bryce Lelbach
  4. Distributed under the Boost Software License, Version 1.0. (See accompanying
  5. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  6. ==============================================================================*/
  7. #if !defined(BOOST_SPIRIT_REAL_APRIL_18_2006_0850AM)
  8. #define BOOST_SPIRIT_REAL_APRIL_18_2006_0850AM
  9. #if defined(_MSC_VER)
  10. #pragma once
  11. #endif
  12. #include <boost/spirit/home/qi/skip_over.hpp>
  13. #include <boost/spirit/home/qi/detail/enable_lit.hpp>
  14. #include <boost/spirit/home/qi/meta_compiler.hpp>
  15. #include <boost/spirit/home/qi/parser.hpp>
  16. #include <boost/spirit/home/qi/numeric/real_policies.hpp>
  17. #include <boost/spirit/home/qi/numeric/numeric_utils.hpp>
  18. #include <boost/spirit/home/qi/numeric/detail/real_impl.hpp>
  19. #include <boost/spirit/home/support/common_terminals.hpp>
  20. #include <boost/type_traits/is_same.hpp>
  21. namespace boost { namespace spirit
  22. {
  23. namespace qi
  24. {
  25. ///////////////////////////////////////////////////////////////////////
  26. // forward declaration only
  27. template <typename T>
  28. struct real_policies;
  29. ///////////////////////////////////////////////////////////////////////
  30. // This is the class that the user can instantiate directly in
  31. // order to create a customized real parser
  32. template <typename T = double, typename Policies = real_policies<T> >
  33. struct real_parser
  34. : spirit::terminal<tag::stateful_tag<Policies, tag::double_, T> >
  35. {
  36. typedef tag::stateful_tag<Policies, tag::double_, T> tag_type;
  37. real_parser() {}
  38. real_parser(Policies const& p)
  39. : spirit::terminal<tag_type>(p) {}
  40. };
  41. }
  42. ///////////////////////////////////////////////////////////////////////////
  43. // Enablers
  44. ///////////////////////////////////////////////////////////////////////////
  45. template <> // enables float_
  46. struct use_terminal<qi::domain, tag::float_>
  47. : mpl::true_ {};
  48. template <> // enables double_
  49. struct use_terminal<qi::domain, tag::double_>
  50. : mpl::true_ {};
  51. template <> // enables long_double
  52. struct use_terminal<qi::domain, tag::long_double>
  53. : mpl::true_ {};
  54. ///////////////////////////////////////////////////////////////////////////
  55. template <typename A0> // enables lit(n)
  56. struct use_terminal<qi::domain
  57. , terminal_ex<tag::lit, fusion::vector1<A0> >
  58. , typename enable_if<is_same<A0, float> >::type>
  59. : mpl::true_ {};
  60. template <typename A0> // enables lit(n)
  61. struct use_terminal<qi::domain
  62. , terminal_ex<tag::lit, fusion::vector1<A0> >
  63. , typename enable_if<is_same<A0, double> >::type>
  64. : mpl::true_ {};
  65. template <typename A0> // enables lit(n)
  66. struct use_terminal<qi::domain
  67. , terminal_ex<tag::lit, fusion::vector1<A0> >
  68. , typename enable_if<is_same<A0, long double> >::type>
  69. : mpl::true_ {};
  70. ///////////////////////////////////////////////////////////////////////////
  71. template <typename A0> // enables float_(...)
  72. struct use_terminal<qi::domain
  73. , terminal_ex<tag::float_, fusion::vector1<A0> >
  74. > : mpl::true_ {};
  75. template <typename A0> // enables double_(...)
  76. struct use_terminal<qi::domain
  77. , terminal_ex<tag::double_, fusion::vector1<A0> >
  78. > : mpl::true_ {};
  79. template <typename A0> // enables long_double(...)
  80. struct use_terminal<qi::domain
  81. , terminal_ex<tag::long_double, fusion::vector1<A0> >
  82. > : mpl::true_ {};
  83. template <> // enables *lazy* float_(...)
  84. struct use_lazy_terminal<qi::domain, tag::float_, 1>
  85. : mpl::true_ {};
  86. template <> // enables *lazy* double_(...)
  87. struct use_lazy_terminal<qi::domain, tag::double_, 1>
  88. : mpl::true_ {};
  89. template <> // enables *lazy* long_double_(...)
  90. struct use_lazy_terminal<qi::domain, tag::long_double, 1>
  91. : mpl::true_ {};
  92. ///////////////////////////////////////////////////////////////////////////
  93. // enables custom real_parser
  94. template <typename T, typename Policies>
  95. struct use_terminal<qi::domain
  96. , tag::stateful_tag<Policies, tag::double_, T> >
  97. : mpl::true_ {};
  98. // enables custom real_parser(...)
  99. template <typename T, typename Policies, typename A0>
  100. struct use_terminal<qi::domain
  101. , terminal_ex<tag::stateful_tag<Policies, tag::double_, T>
  102. , fusion::vector1<A0> > >
  103. : mpl::true_ {};
  104. // enables *lazy* custom real_parser(...)
  105. template <typename T, typename Policies>
  106. struct use_lazy_terminal<
  107. qi::domain
  108. , tag::stateful_tag<Policies, tag::double_, T>
  109. , 1 // arity
  110. > : mpl::true_ {};
  111. }}
  112. namespace boost { namespace spirit { namespace qi
  113. {
  114. #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
  115. using spirit::float_;
  116. using spirit::double_;
  117. using spirit::long_double;
  118. using spirit::lit; // lit(1.0) is equivalent to 1.0
  119. #endif
  120. using spirit::float_type;
  121. using spirit::double_type;
  122. using spirit::long_double_type;
  123. using spirit::lit_type;
  124. ///////////////////////////////////////////////////////////////////////////
  125. // This is the actual real number parser
  126. ///////////////////////////////////////////////////////////////////////////
  127. template <typename T, typename RealPolicies = real_policies<T> >
  128. struct any_real_parser
  129. : primitive_parser<any_real_parser<T, RealPolicies> >
  130. {
  131. template <typename Context, typename Iterator>
  132. struct attribute
  133. {
  134. typedef T type;
  135. };
  136. template <typename Iterator, typename Context, typename Skipper>
  137. bool parse(Iterator& first, Iterator const& last
  138. , Context& /*context*/, Skipper const& skipper
  139. , T& attr_) const
  140. {
  141. typedef detail::real_impl<T, RealPolicies> extract;
  142. qi::skip_over(first, last, skipper);
  143. return extract::parse(first, last, attr_, RealPolicies());
  144. }
  145. template <typename Iterator, typename Context
  146. , typename Skipper, typename Attribute>
  147. bool parse(Iterator& first, Iterator const& last
  148. , Context& context, Skipper const& skipper
  149. , Attribute& attr_param) const
  150. {
  151. // this case is called when Attribute is not T
  152. T attr_;
  153. if (parse(first, last, context, skipper, attr_))
  154. {
  155. traits::assign_to(attr_, attr_param);
  156. return true;
  157. }
  158. return false;
  159. }
  160. template <typename Context>
  161. info what(Context& /*context*/) const
  162. {
  163. return info("real");
  164. }
  165. };
  166. template <typename T, typename RealPolicies = real_policies<T>
  167. , bool no_attribute = true>
  168. struct literal_real_parser
  169. : primitive_parser<literal_real_parser<T, RealPolicies, no_attribute> >
  170. {
  171. template <typename Value>
  172. literal_real_parser(Value const& n) : n_(n) {}
  173. template <typename Context, typename Iterator>
  174. struct attribute
  175. : mpl::if_c<no_attribute, unused_type, T>
  176. {};
  177. template <typename Iterator, typename Context
  178. , typename Skipper, typename Attribute>
  179. bool parse(Iterator& first, Iterator const& last
  180. , Context&, Skipper const& skipper
  181. , Attribute& attr_param) const
  182. {
  183. typedef detail::real_impl<T, RealPolicies> extract;
  184. qi::skip_over(first, last, skipper);
  185. Iterator save = first;
  186. T attr_;
  187. if (extract::parse(first, last, attr_, RealPolicies()) &&
  188. (attr_ == n_))
  189. {
  190. traits::assign_to(attr_, attr_param);
  191. return true;
  192. }
  193. first = save;
  194. return false;
  195. }
  196. template <typename Context>
  197. info what(Context& /*context*/) const
  198. {
  199. return info("real");
  200. }
  201. T n_;
  202. };
  203. ///////////////////////////////////////////////////////////////////////////
  204. // Parser generators: make_xxx function (objects)
  205. ///////////////////////////////////////////////////////////////////////////
  206. template <typename T, typename Policies = real_policies<T> >
  207. struct make_real
  208. {
  209. typedef any_real_parser<T, Policies> result_type;
  210. result_type operator()(unused_type, unused_type) const
  211. {
  212. return result_type();
  213. }
  214. };
  215. template <typename T, typename Policies = real_policies<T> >
  216. struct make_direct_real
  217. {
  218. typedef literal_real_parser<T, Policies, false> result_type;
  219. template <typename Terminal>
  220. result_type operator()(Terminal const& term, unused_type) const
  221. {
  222. return result_type(T(fusion::at_c<0>(term.args)));
  223. }
  224. };
  225. template <typename T, typename Policies = real_policies<T> >
  226. struct make_literal_real
  227. {
  228. typedef literal_real_parser<T, Policies> result_type;
  229. template <typename Terminal>
  230. result_type operator()(Terminal const& term, unused_type) const
  231. {
  232. return result_type(fusion::at_c<0>(term.args));
  233. }
  234. };
  235. ///////////////////////////////////////////////////////////////////////////
  236. template <typename Modifiers, typename A0>
  237. struct make_primitive<
  238. terminal_ex<tag::lit, fusion::vector1<A0> >
  239. , Modifiers, typename enable_if<is_same<A0, float> >::type>
  240. : make_literal_real<float> {};
  241. template <typename Modifiers, typename A0>
  242. struct make_primitive<
  243. terminal_ex<tag::lit, fusion::vector1<A0> >
  244. , Modifiers, typename enable_if<is_same<A0, double> >::type>
  245. : make_literal_real<double> {};
  246. template <typename Modifiers, typename A0>
  247. struct make_primitive<
  248. terminal_ex<tag::lit, fusion::vector1<A0> >
  249. , Modifiers, typename enable_if<is_same<A0, long double> >::type>
  250. : make_literal_real<long double> {};
  251. ///////////////////////////////////////////////////////////////////////////
  252. template <typename T, typename Policies, typename Modifiers>
  253. struct make_primitive<
  254. tag::stateful_tag<Policies, tag::double_, T>, Modifiers>
  255. : make_real<T, Policies> {};
  256. template <typename T, typename Policies, typename A0, typename Modifiers>
  257. struct make_primitive<
  258. terminal_ex<tag::stateful_tag<Policies, tag::double_, T>
  259. , fusion::vector1<A0> >, Modifiers>
  260. : make_direct_real<T, Policies> {};
  261. ///////////////////////////////////////////////////////////////////////////
  262. template <typename Modifiers>
  263. struct make_primitive<tag::float_, Modifiers>
  264. : make_real<float> {};
  265. template <typename Modifiers, typename A0>
  266. struct make_primitive<
  267. terminal_ex<tag::float_
  268. , fusion::vector1<A0> >, Modifiers>
  269. : make_direct_real<float> {};
  270. ///////////////////////////////////////////////////////////////////////////
  271. template <typename Modifiers>
  272. struct make_primitive<tag::double_, Modifiers>
  273. : make_real<double> {};
  274. template <typename Modifiers, typename A0>
  275. struct make_primitive<
  276. terminal_ex<tag::double_
  277. , fusion::vector1<A0> >, Modifiers>
  278. : make_direct_real<double> {};
  279. ///////////////////////////////////////////////////////////////////////////
  280. template <typename Modifiers>
  281. struct make_primitive<tag::long_double, Modifiers>
  282. : make_real<long double> {};
  283. template <typename Modifiers, typename A0>
  284. struct make_primitive<
  285. terminal_ex<tag::long_double
  286. , fusion::vector1<A0> >, Modifiers>
  287. : make_direct_real<long double> {};
  288. }}}
  289. #endif