ceph/src/boost/libs/spirit/include/boost/spirit/home/qi/numeric/bool.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Hartmut Kaiser
   3     Copyright (c) 2011      Bryce Lelbach
   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 #if !defined(SPIRIT_QI_BOOL_SEP_29_2009_0709AM)
   9 #define SPIRIT_QI_BOOL_SEP_29_2009_0709AM
  10
  11 #if defined(_MSC_VER)
  12 #pragma once
  13 #endif
  14
  15 #include <boost/spirit/home/qi/skip_over.hpp>
  16 #include <boost/spirit/home/qi/detail/enable_lit.hpp>
  17 #include <boost/spirit/home/qi/meta_compiler.hpp>
  18 #include <boost/spirit/home/qi/parser.hpp>
  19 #include <boost/spirit/home/qi/numeric/bool_policies.hpp>
  20 #include <boost/spirit/home/support/common_terminals.hpp>
  21 #include <boost/mpl/assert.hpp>
  22 #include <boost/detail/workaround.hpp>
  23 #include <boost/type_traits/is_same.hpp>
  24
  25 namespace boost { namespace spirit
  26 {
  27     namespace qi
  28     {
  29         ///////////////////////////////////////////////////////////////////////
  30         // forward declaration only
  31         template <typename T>
  32         struct bool_policies;
  33
  34         ///////////////////////////////////////////////////////////////////////
  35         // This is the class that the user can instantiate directly in
  36         // order to create a customized bool parser
  37         template <typename T, typename BoolPolicies = bool_policies<T> >
  38         struct bool_parser
  39           : spirit::terminal<tag::stateful_tag<BoolPolicies, tag::bool_, T> >
  40         {
  41             typedef tag::stateful_tag<BoolPolicies, tag::bool_, T> tag_type;
  42
  43             bool_parser() {}
  44             bool_parser(BoolPolicies const& data)
  45               : spirit::terminal<tag_type>(data) {}
  46         };
  47     }
  48
  49     ///////////////////////////////////////////////////////////////////////////
  50     // Enablers
  51     ///////////////////////////////////////////////////////////////////////////
  52     template <> // enables bool_
  53     struct use_terminal<qi::domain, tag::bool_>
  54       : mpl::true_ {};
  55
  56     template <> // enables true_
  57     struct use_terminal<qi::domain, tag::true_>
  58       : mpl::true_ {};
  59
  60     template <> // enables false_
  61     struct use_terminal<qi::domain, tag::false_>
  62       : mpl::true_ {};
  63
  64     ///////////////////////////////////////////////////////////////////////////
  65     template <typename A0> // enables lit(...)
  66     struct use_terminal<qi::domain
  67         , terminal_ex<tag::lit, fusion::vector1<A0> >
  68         , typename enable_if<is_same<A0, bool> >::type>
  69       : mpl::true_ {};
  70
  71     ///////////////////////////////////////////////////////////////////////////
  72     template <typename A0> // enables bool_(...)
  73     struct use_terminal<qi::domain
  74       , terminal_ex<tag::bool_, fusion::vector1<A0> >
  75     > : mpl::true_ {};
  76
  77     template <> // enables *lazy* bool_(...)
  78     struct use_lazy_terminal<qi::domain, tag::bool_, 1>
  79       : mpl::true_ {};
  80
  81     ///////////////////////////////////////////////////////////////////////////
  82     // enables any custom bool_parser
  83     template <typename T, typename BoolPolicies>
  84     struct use_terminal<qi::domain
  85         , tag::stateful_tag<BoolPolicies, tag::bool_, T> >
  86       : mpl::true_ {};
  87
  88     // enables any custom bool_parser(...)
  89     template <typename T, typename BoolPolicies, typename A0>
  90     struct use_terminal<qi::domain
  91         , terminal_ex<tag::stateful_tag<BoolPolicies, tag::bool_, T>
  92         , fusion::vector1<A0> > >
  93       : mpl::true_ {};
  94
  95     // enables *lazy* custom bool_parser(...)
  96     template <typename T, typename BoolPolicies>
  97     struct use_lazy_terminal<
  98         qi::domain
  99       , tag::stateful_tag<BoolPolicies, tag::bool_, T>
 100       , 1 // arity
 101     > : mpl::true_ {};
 102 }}
 103
 104 namespace boost { namespace spirit { namespace qi
 105 {
 106 #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
 107     using spirit::bool_;
 108     using spirit::true_;
 109     using spirit::false_;
 110     using spirit::lit;    // lit(true) is equivalent to true
 111 #endif
 112     using spirit::bool_type;
 113     using spirit::true_type;
 114     using spirit::false_type;
 115     using spirit::lit_type;
 116
 117     namespace detail
 118     {
 119         template <typename T, typename BoolPolicies>
 120         struct bool_impl
 121         {
 122             template <typename Iterator, typename Attribute>
 123             static bool parse(Iterator& first, Iterator const& last
 124               , Attribute& attr, BoolPolicies const& p, bool allow_true = true
 125               , bool disallow_false = false)
 126             {
 127                 if (first == last)
 128                     return false;
 129
 130 #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1600))
 131                 p; // suppresses warning: C4100: 'p' : unreferenced formal parameter
 132 #endif
 133                 return (allow_true && p.parse_true(first, last, attr)) ||
 134                        (!disallow_false && p.parse_false(first, last, attr));
 135             }
 136         };
 137     }
 138
 139     ///////////////////////////////////////////////////////////////////////////
 140     // This actual boolean parser
 141     ///////////////////////////////////////////////////////////////////////////
 142     template <typename T, typename BoolPolicies = bool_policies<T> >
 143     struct any_bool_parser
 144       : primitive_parser<any_bool_parser<T, BoolPolicies> >
 145     {
 146         template <typename Context, typename Iterator>
 147         struct attribute
 148         {
 149             typedef T type;
 150         };
 151
 152         template <typename Iterator, typename Context
 153           , typename Skipper, typename Attribute>
 154         bool parse(Iterator& first, Iterator const& last
 155           , Context& /*context*/, Skipper const& skipper
 156           , Attribute& attr_) const
 157         {
 158             typedef detail::bool_impl<T, BoolPolicies> extract;
 159             qi::skip_over(first, last, skipper);
 160             return extract::parse(first, last, attr_, BoolPolicies());
 161         }
 162
 163         template <typename Context>
 164         info what(Context& /*context*/) const
 165         {
 166             return info("boolean");
 167         }
 168     };
 169
 170     template <typename T, typename BoolPolicies = bool_policies<T>
 171             , bool no_attribute = true>
 172     struct literal_bool_parser
 173       : primitive_parser<literal_bool_parser<T, BoolPolicies, no_attribute> >
 174     {
 175         template <typename Value>
 176         literal_bool_parser(Value const& n) : n_(n) {}
 177
 178         template <typename Context, typename Iterator>
 179         struct attribute
 180           : mpl::if_c<no_attribute, unused_type, T>
 181         {};
 182
 183         template <typename Iterator, typename Context
 184           , typename Skipper, typename Attribute>
 185         bool parse(Iterator& first, Iterator const& last
 186           , Context& /*context*/, Skipper const& skipper
 187           , Attribute& attr_) const
 188         {
 189             typedef detail::bool_impl<T, BoolPolicies> extract;
 190             qi::skip_over(first, last, skipper);
 191             return extract::parse(first, last, attr_, BoolPolicies(), n_, n_);
 192         }
 193
 194         template <typename Context>
 195         info what(Context& /*context*/) const
 196         {
 197             return info("boolean");
 198         }
 199
 200         T n_;
 201     };
 202
 203     ///////////////////////////////////////////////////////////////////////////
 204     // Parser generators: make_xxx function (objects)
 205     ///////////////////////////////////////////////////////////////////////////
 206     template <typename T, typename Modifiers
 207             , typename Policies = bool_policies<T> >
 208     struct make_bool
 209     {
 210         typedef has_modifier<Modifiers, tag::char_code_base<tag::no_case> >
 211             no_case;
 212
 213         typedef typename mpl::if_<
 214             mpl::and_<
 215                 no_case
 216               , is_same<bool_policies<T>, Policies>
 217             >
 218           , any_bool_parser<T, no_case_bool_policies<T> >
 219           , any_bool_parser<T, Policies> >::type
 220         result_type;
 221
 222         result_type operator()(unused_type, unused_type) const
 223         {
 224             return result_type();
 225         }
 226     };
 227
 228     template <typename T, typename Modifiers
 229             , typename Policies = bool_policies<T> >
 230     struct make_direct_bool
 231     {
 232         typedef has_modifier<Modifiers, tag::char_code_base<tag::no_case> >
 233             no_case;
 234
 235         typedef typename mpl::if_<
 236             mpl::and_<
 237                 no_case
 238               , is_same<bool_policies<T>, Policies>
 239             >
 240           , literal_bool_parser<T, no_case_bool_policies<T>, false>
 241           , literal_bool_parser<T, Policies, false> >::type
 242         result_type;
 243
 244         template <typename Terminal>
 245         result_type operator()(Terminal const& term, unused_type) const
 246         {
 247             return result_type(fusion::at_c<0>(term.args));
 248         }
 249     };
 250
 251     template <typename T, typename Modifiers, bool b
 252             , typename Policies = bool_policies<T> >
 253     struct make_predefined_direct_bool
 254     {
 255         typedef has_modifier<Modifiers, tag::char_code_base<tag::no_case> >
 256             no_case;
 257
 258         typedef typename mpl::if_<
 259             mpl::and_<
 260                 no_case
 261               , is_same<bool_policies<T>, Policies>
 262             >
 263           , literal_bool_parser<T, no_case_bool_policies<T>, false>
 264           , literal_bool_parser<T, Policies, false> >::type
 265         result_type;
 266
 267         result_type operator()(unused_type, unused_type) const
 268         {
 269             return result_type(b);
 270         }
 271     };
 272
 273     template <typename T, typename Modifiers
 274             , typename Policies = bool_policies<T> >
 275     struct make_literal_bool
 276     {
 277         typedef has_modifier<Modifiers, tag::char_code_base<tag::no_case> >
 278             no_case;
 279
 280         typedef typename mpl::if_<
 281             mpl::and_<
 282                 no_case
 283               , is_same<bool_policies<T>, Policies>
 284             >
 285           , literal_bool_parser<T, no_case_bool_policies<T> >
 286           , literal_bool_parser<T, Policies> >::type
 287         result_type;
 288
 289         template <typename Terminal>
 290         result_type operator()(Terminal const& term, unused_type) const
 291         {
 292             return result_type(fusion::at_c<0>(term.args));
 293         }
 294     };
 295
 296     ///////////////////////////////////////////////////////////////////////////
 297     template <typename Modifiers, typename A0>
 298     struct make_primitive<
 299           terminal_ex<tag::lit, fusion::vector1<A0> >
 300         , Modifiers, typename enable_if<is_same<A0, bool> >::type>
 301       : make_literal_bool<bool, Modifiers> {};
 302
 303     ///////////////////////////////////////////////////////////////////////////
 304     template <typename Modifiers>
 305     struct make_primitive<tag::false_, Modifiers>
 306       : make_predefined_direct_bool<bool, Modifiers, false>
 307     {};
 308
 309     template <typename Modifiers>
 310     struct make_primitive<tag::true_, Modifiers>
 311       : make_predefined_direct_bool<bool, Modifiers, true>
 312     {};
 313
 314     ///////////////////////////////////////////////////////////////////////////
 315     template <typename T, typename Policies, typename Modifiers>
 316     struct make_primitive<
 317         tag::stateful_tag<Policies, tag::bool_, T>, Modifiers>
 318       : make_bool<T, Modifiers, Policies> {};
 319
 320     template <typename T, typename Policies, typename A0, typename Modifiers>
 321     struct make_primitive<
 322         terminal_ex<tag::stateful_tag<Policies, tag::bool_, T>
 323       , fusion::vector1<A0> >, Modifiers>
 324       : make_direct_bool<T, Modifiers, Policies> {};
 325
 326     ///////////////////////////////////////////////////////////////////////////
 327     template <typename Modifiers>
 328     struct make_primitive<tag::bool_, Modifiers>
 329       : make_bool<bool, Modifiers> {};
 330
 331     template <typename Modifiers, typename A0>
 332     struct make_primitive<
 333         terminal_ex<tag::bool_
 334       , fusion::vector1<A0> >, Modifiers>
 335       : make_direct_bool<bool, Modifiers> {};
 336 }}}
 337
 338 #endif