ceph/src/boost/libs/spirit/include/boost/spirit/home/x3/numeric/real.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2014 Joel de Guzman
   3
   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_X3_REAL_APRIL_18_2006_0850AM)
   8 #define BOOST_SPIRIT_X3_REAL_APRIL_18_2006_0850AM
   9
  10 #include <boost/spirit/home/x3/core/parser.hpp>
  11 #include <boost/spirit/home/x3/core/skip_over.hpp>
  12 #include <boost/spirit/home/x3/numeric/real_policies.hpp>
  13 #include <boost/spirit/home/x3/support/numeric_utils/extract_real.hpp>
  14
  15 namespace boost { namespace spirit { namespace x3
  16 {
  17     template <typename T, typename RealPolicies = real_policies<T> >
  18     struct real_parser : parser<real_parser<T, RealPolicies> >
  19     {
  20         typedef T attribute_type;
  21         static bool const has_attribute = true;
  22
  23         real_parser()
  24                 : policies() {}
  25
  26         real_parser(RealPolicies const& policies)
  27                 : policies(policies) {}
  28
  29         template <typename Iterator, typename Context>
  30         bool parse(Iterator& first, Iterator const& last
  31           , Context& context, unused_type, T& attr_) const
  32         {
  33             x3::skip_over(first, last, context);
  34             return extract_real<T, RealPolicies>::parse(first, last, attr_, policies);
  35         }
  36
  37         template <typename Iterator, typename Context, typename Attribute>
  38         bool parse(Iterator& first, Iterator const& last
  39           , Context& context, unused_type, Attribute& attr_param) const
  40         {
  41             // this case is called when Attribute is not T
  42             T attr_;
  43             if (parse(first, last, context, unused, attr_))
  44             {
  45                 traits::move_to(attr_, attr_param);
  46                 return true;
  47             }
  48             return false;
  49         }
  50
  51         RealPolicies policies;
  52     };
  53
  54     typedef real_parser<float> float_type;
  55     float_type const float_ = {};
  56
  57     typedef real_parser<double> double_type;
  58     double_type const double_ = {};
  59
  60 }}}
  61
  62 #endif