boost/exception/to_string.hpp

   1 //Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc.
   2
   3 //Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef UUID_7E48761AD92811DC9011477D56D89593
   7 #define UUID_7E48761AD92811DC9011477D56D89593
   8
   9 #include <boost/utility/enable_if.hpp>
  10 #include <boost/exception/detail/is_output_streamable.hpp>
  11 #include <sstream>
  12
  13 namespace
  14 boost
  15     {
  16     namespace
  17     to_string_detail
  18         {
  19         template <class T>
  20         typename disable_if<is_output_streamable<T>,char>::type to_string( T const & );
  21
  22         template <class,bool IsOutputStreamable>
  23         struct has_to_string_impl;
  24
  25         template <class T>
  26         struct
  27         has_to_string_impl<T,true>
  28             {
  29             enum e { value=1 };
  30             };
  31
  32         template <class T>
  33         struct
  34         has_to_string_impl<T,false>
  35             {
  36             static T const & f();
  37             enum e { value=1!=sizeof(to_string(f())) };
  38             };
  39         }
  40
  41     template <class T>
  42     inline
  43     typename enable_if<is_output_streamable<T>,std::string>::type
  44     to_string( T const & x )
  45         {
  46         std::ostringstream out;
  47         out << x;
  48         return out.str();
  49         }
  50
  51     template <class T>
  52     struct
  53     has_to_string
  54         {
  55         enum e { value=to_string_detail::has_to_string_impl<T,is_output_streamable<T>::value>::value };
  56         };
  57
  58     template <class T,class U>
  59     inline
  60     std::string
  61     to_string( std::pair<T,U> const & x )
  62         {
  63         return std::string("(") + to_string(x.first) + ',' + to_string(x.second) + ')';
  64         }
  65
  66     inline
  67     std::string
  68     to_string( std::exception const & x )
  69         {
  70         return x.what();
  71         }
  72     }
  73
  74 #endif