ceph/src/boost/boost/spirit/home/x3/support/traits/print_token.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2014 Joel de Guzman
   3     Copyright (c) 2001-2011 Hartmut Kaiser
   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(BOOST_SPIRIT_X3_PRINT_TOKEN_JANUARY_20_2013_0814AM)
   9 #define BOOST_SPIRIT_X3_PRINT_TOKEN_JANUARY_20_2013_0814AM
  10
  11 #include <boost/mpl/if.hpp>
  12 #include <boost/mpl/and.hpp>
  13 #include <boost/type_traits/is_convertible.hpp>
  14 #include <cctype>
  15 #include <ios>
  16
  17 namespace boost { namespace spirit { namespace x3 { namespace traits
  18 {
  19     ///////////////////////////////////////////////////////////////////////////
  20     // generate debug output for lookahead token (character) stream
  21     namespace detail
  22     {
  23         struct token_printer_debug_for_chars
  24         {
  25             template<typename Out, typename Char>
  26             static void print(Out& o, Char c)
  27             {
  28                 using namespace std;    // allow for ADL to find the proper iscntrl
  29
  30                 switch (c)
  31                 {
  32                     case '\a': o << "\\a"; break;
  33                     case '\b': o << "\\b"; break;
  34                     case '\f': o << "\\f"; break;
  35                     case '\n': o << "\\n"; break;
  36                     case '\r': o << "\\r"; break;
  37                     case '\t': o << "\\t"; break;
  38                     case '\v': o << "\\v"; break;
  39                     default:
  40                         if (c >= 0 && c < 127)
  41                         {
  42                           if (iscntrl(c))
  43                             o << "\\" << std::oct << int(c);
  44                           else if (isprint(c))
  45                             o << char(c);
  46                           else
  47                             o << "\\x" << std::hex << int(c);
  48                         }
  49                         else
  50                           o << "\\x" << std::hex << int(c);
  51                 }
  52             }
  53         };
  54
  55         // for token types where the comparison with char constants wouldn't work
  56         struct token_printer_debug
  57         {
  58             template<typename Out, typename T>
  59             static void print(Out& o, T const& val)
  60             {
  61                 o << val;
  62             }
  63         };
  64     }
  65
  66     template <typename T, typename Enable = void>
  67     struct token_printer_debug
  68       : mpl::if_<
  69             mpl::and_<
  70                 is_convertible<T, char>, is_convertible<char, T> >
  71           , detail::token_printer_debug_for_chars
  72           , detail::token_printer_debug>::type
  73     {};
  74
  75     template <typename Out, typename T>
  76     inline void print_token(Out& out, T const& val)
  77     {
  78         // allow to customize the token printer routine
  79         token_printer_debug<T>::print(out, val);
  80     }
  81 }}}}
  82
  83 #endif