Synopsis

#include <boost/pattern_except.hpp>

The class bad_expression defines the type of objects thrown as exceptions to report errors during the conversion from a string representing a regular expression to a finite state machine.  

namespace boost{

class bad_pattern : public std::runtime_error
{
public:
   explicit bad_pattern(const std::string& s) : std::runtime_error(s){};
};

class bad_expression : public bad_pattern
{
public:
   bad_expression(const std::string& s) : bad_pattern(s) {}
};


} // namespace boost

Description

bad_expression(const string& what_arg);

Effects: Constructs an object of class bad_expression.

Postcondition: strcmp(what(), what_arg.c_str()) == 0.

Footnotes: the class bad_pattern forms the base class for all pattern-matching exceptions, of which bad_expression is one. The choice of std::runtime_error as the base class for bad_pattern is moot; depending upon how the library is used exceptions may be either logic errors (programmer supplied expressions) or run time errors (user supplied expressions).

Revised 24 Oct 2003

© Copyright John Maddock 1998- 2003

Use, modification and distribution are subject to the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)