Files
boost_conversion/include/boost/lexical_cast.hpp
T
2002-01-20 20:08:46 +00:00

77 lines
2.2 KiB
C++

// boost lexical_cast.hpp header -------------------------------------------//
// See http://www.boost.org for most recent version including documentation.
#ifndef BOOST_LEXICAL_CAST_INCLUDED
#define BOOST_LEXICAL_CAST_INCLUDED
// what: lexical_cast custom keyword cast
// who: contributed by Kevlin Henney, with alternative naming, behaviors
// and fixes contributed by Dave Abrahams, Daryle Walker and other
// Boosters on the list
// when: November 2000
// where: tested with MSVC 6.0, BCC 5.5, and g++ 2.91
#include <boost/config.hpp>
// Some sstream implementations are broken for the purposes of lexical cast.
# if defined(BOOST_NO_STRINGSTREAM)
# define BOOST_LEXICAL_CAST_USE_STRSTREAM
# endif
#ifdef BOOST_LEXICAL_CAST_USE_STRSTREAM
# include <strstream>
#else
# include <sstream>
#endif
#include <typeinfo>
namespace boost
{
// exception used to indicate runtime lexical_cast failure
class bad_lexical_cast : public std::bad_cast
{
public:
// constructors, destructors, and assignment operator defaulted
// function inlined for brevity and consistency with rest of library
virtual const char * what() const throw()
{
return "bad lexical cast: "
"source type value could not be interpreted as target";
}
};
template<typename Target, typename Source>
Target lexical_cast(Source arg)
{
# ifdef BOOST_LEXICAL_CAST_USE_STRSTREAM
std::strstream interpreter; // for out-of-the-box g++ 2.95.2
# else
std::stringstream interpreter;
# endif
Target result;
if(!(interpreter << arg) || !(interpreter >> result) ||
!(interpreter >> std::ws).eof())
throw bad_lexical_cast();
return result;
}
}
// Copyright Kevlin Henney, 2000, 2001, 2002. All rights reserved.
//
// Permission to use, copy, modify, and distribute this software for any
// purpose is hereby granted without fee, provided that this copyright and
// permissions notice appear in all copies and derivatives.
//
// This software is provided "as is" without express or implied warranty.
#ifdef BOOST_LEXICAL_CAST_USE_STRSTREAM
# undef BOOST_LEXICAL_CAST_USE_STRSTREAM
#endif
#endif