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
  16 namespace boost { namespace spirit { namespace x3 { namespace traits
  17 {
  18     ///////////////////////////////////////////////////////////////////////////
  19     // generate debug output for lookahead token (character) stream
  20     namespace detail
  21     {
  22         struct token_printer_debug_for_chars
  23         {
  24             template<typename Out, typename Char>
  25             static void print(Out& o, Char c)
  26             {
  27                 using namespace std;    // allow for ADL to find the proper iscntrl
  28
  29                 switch (c)
  30                 {
  31                     case '\a': o << "\\a"; break;
  32                     case '\b': o << "\\b"; break;
  33                     case '\f': o << "\\f"; break;
  34                     case '\n': o << "\\n"; break;
  35                     case '\r': o << "\\r"; break;
  36                     case '\t': o << "\\t"; break;
  37                     case '\v': o << "\\v"; break;
  38                     default:
  39                         if (c >= 0 && c < 127 && iscntrl(c))
  40                             o << "\\" << std::oct << int(c);
  41                         else
  42                             o << Char(c);
  43                 }
  44             }
  45         };
  46
  47         // for token types where the comparison with char constants wouldn't work
  48         struct token_printer_debug
  49         {
  50             template<typename Out, typename T>
  51             static void print(Out& o, T const& val)
  52             {
  53                 o << val;
  54             }
  55         };
  56     }
  57
  58     template <typename T, typename Enable = void>
  59     struct token_printer_debug
  60       : mpl::if_<
  61             mpl::and_<
  62                 is_convertible<T, char>, is_convertible<char, T> >
  63           , detail::token_printer_debug_for_chars
  64           , detail::token_printer_debug>::type
  65     {};
  66
  67     template <typename Out, typename T>
  68     inline void print_token(Out& out, T const& val)
  69     {
  70         // allow to customize the token printer routine
  71         token_printer_debug<T>::print(out, val);
  72     }
  73 }}}}
  74
  75 #endif