boost/variant/bad_visit.hpp

   1 //-----------------------------------------------------------------------------
   2 // boost variant/bad_visit.hpp header file
   3 // See http://www.boost.org for updates, documentation, and revision history.
   4 //-----------------------------------------------------------------------------
   5 //
   6 // Copyright (c) 2002-2003
   7 // Eric Friedman
   8 //
   9 // Distributed under the Boost Software License, Version 1.0. (See
  10 // accompanying file LICENSE_1_0.txt or copy at
  11 // http://www.boost.org/LICENSE_1_0.txt)
  12
  13 #ifndef BOOST_VARIANT_BAD_VISIT_HPP
  14 #define BOOST_VARIANT_BAD_VISIT_HPP
  15
  16 #include <exception>
  17
  18 namespace boost {
  19
  20 //////////////////////////////////////////////////////////////////////////
  21 // class bad_visit
  22 //
  23 // Exception thrown when a visitation attempt via apply_visitor fails due
  24 // to invalid visited subtype or contents.
  25 //
  26 struct bad_visit
  27     : std::exception
  28 {
  29 public: // std::exception interface
  30
  31     virtual const char * what() const throw()
  32     {
  33         return "boost::bad_visit: "
  34                "failed visitation using boost::apply_visitor";
  35     }
  36
  37 };
  38
  39 } // namespace boost
  40
  41 #endif // BOOST_VARIANT_BAD_VISIT_HPP