sl@0: #ifndef BOOST_LEXICAL_CAST_INCLUDED
sl@0: #define BOOST_LEXICAL_CAST_INCLUDED
sl@0: 
sl@0: // Boost lexical_cast.hpp header  -------------------------------------------//
sl@0: //
sl@0: // See http://www.boost.org for most recent version including documentation.
sl@0: // See end of this header for rights and permissions.
sl@0: //
sl@0: // what:  lexical_cast custom keyword cast
sl@0: // who:   contributed by Kevlin Henney,
sl@0: //        enhanced with contributions from Terje Slettebų,
sl@0: //        with additional fixes and suggestions from Gennaro Prota,
sl@0: //        Beman Dawes, Dave Abrahams, Daryle Walker, Peter Dimov,
sl@0: //        and other Boosters
sl@0: // when:  November 2000, March 2003, June 2005
sl@0: 
sl@0: #include <cstddef>
sl@0: #include <string>
sl@0: #include <typeinfo>
sl@0: #include <boost/config.hpp>
sl@0: #include <boost/limits.hpp>
sl@0: #include <boost/throw_exception.hpp>
sl@0: #include <boost/type_traits/is_pointer.hpp>
sl@0: 
sl@0: #ifdef BOOST_NO_STRINGSTREAM
sl@0: #include <strstream>
sl@0: #else
sl@0: #include <sstream>
sl@0: #endif
sl@0: 
sl@0: #if defined(BOOST_NO_STRINGSTREAM) || \
sl@0:     defined(BOOST_NO_STD_WSTRING) || \
sl@0:     defined(BOOST_NO_STD_LOCALE) 
sl@0: #define DISABLE_WIDE_CHAR_SUPPORT
sl@0: #endif
sl@0: 
sl@0: namespace boost
sl@0: {
sl@0:     // exception used to indicate runtime lexical_cast failure
sl@0:     class bad_lexical_cast : public std::bad_cast
sl@0:     {
sl@0:     public:
sl@0:         bad_lexical_cast() :
sl@0:         source(&typeid(void)), target(&typeid(void))
sl@0:         {
sl@0:         }
sl@0:         bad_lexical_cast(
sl@0:             const std::type_info &source_type,
sl@0:             const std::type_info &target_type) :
sl@0:             source(&source_type), target(&target_type)
sl@0:         {
sl@0:         }
sl@0:         const std::type_info &source_type() const
sl@0:         {
sl@0:             return *source;
sl@0:         }
sl@0:         const std::type_info &target_type() const
sl@0:         {
sl@0:             return *target;
sl@0:         }
sl@0:         virtual const char *what() const throw()
sl@0:         {
sl@0:             return "bad lexical cast: "
sl@0:                    "source type value could not be interpreted as target";
sl@0:         }
sl@0:         virtual ~bad_lexical_cast() throw()
sl@0:         {
sl@0:         }
sl@0:     private:
sl@0:         const std::type_info *source;
sl@0:         const std::type_info *target;
sl@0:     };
sl@0: 
sl@0:     namespace detail // selectors for choosing stream character type
sl@0:     {
sl@0:         template<typename Type>
sl@0:         struct stream_char
sl@0:         {
sl@0:             typedef char type;
sl@0:         };
sl@0: 
sl@0:         #ifndef DISABLE_WIDE_CHAR_SUPPORT
sl@0: #if !defined(BOOST_NO_INTRINSIC_WCHAR_T)
sl@0:         template<>
sl@0:         struct stream_char<wchar_t>
sl@0:         {
sl@0:             typedef wchar_t type;
sl@0:         };
sl@0: #endif
sl@0: 
sl@0:         template<>
sl@0:         struct stream_char<wchar_t *>
sl@0:         {
sl@0:             typedef wchar_t type;
sl@0:         };
sl@0: 
sl@0:         template<>
sl@0:         struct stream_char<const wchar_t *>
sl@0:         {
sl@0:             typedef wchar_t type;
sl@0:         };
sl@0: 
sl@0:         template<>
sl@0:         struct stream_char<std::wstring>
sl@0:         {
sl@0:             typedef wchar_t type;
sl@0:         };
sl@0:         #endif
sl@0: 
sl@0:         template<typename TargetChar, typename SourceChar>
sl@0:         struct widest_char
sl@0:         {
sl@0:             typedef TargetChar type;
sl@0:         };
sl@0: 
sl@0:         template<>
sl@0:         struct widest_char<char, wchar_t>
sl@0:         {
sl@0:             typedef wchar_t type;
sl@0:         };
sl@0:     }
sl@0:     
sl@0:     namespace detail // stream wrapper for handling lexical conversions
sl@0:     {
sl@0:         template<typename Target, typename Source>
sl@0:         class lexical_stream
sl@0:         {
sl@0:         private:
sl@0:             typedef typename widest_char<
sl@0:                 typename stream_char<Target>::type,
sl@0:                 typename stream_char<Source>::type>::type char_type;
sl@0: 
sl@0:         public:
sl@0:             lexical_stream()
sl@0:             {
sl@0:                 stream.unsetf(std::ios::skipws);
sl@0: 
sl@0:                 if(std::numeric_limits<Target>::is_specialized)
sl@0:                     stream.precision(std::numeric_limits<Target>::digits10 + 1);
sl@0:                 else if(std::numeric_limits<Source>::is_specialized)
sl@0:                     stream.precision(std::numeric_limits<Source>::digits10 + 1);
sl@0:             }
sl@0:             ~lexical_stream()
sl@0:             {
sl@0:                 #if defined(BOOST_NO_STRINGSTREAM)
sl@0:                 stream.freeze(false);
sl@0:                 #endif
sl@0:             }
sl@0:             bool operator<<(const Source &input)
sl@0:             {
sl@0:                 return !(stream << input).fail();
sl@0:             }
sl@0:             template<typename InputStreamable>
sl@0:             bool operator>>(InputStreamable &output)
sl@0:             {
sl@0:                 return !is_pointer<InputStreamable>::value &&
sl@0:                        stream >> output &&
sl@0:                        stream.get() ==
sl@0: #if defined(__GNUC__) && (__GNUC__<3) && defined(BOOST_NO_STD_WSTRING)
sl@0: // GCC 2.9x lacks std::char_traits<>::eof().
sl@0: // We use BOOST_NO_STD_WSTRING to filter out STLport and libstdc++-v3
sl@0: // configurations, which do provide std::char_traits<>::eof().
sl@0:     
sl@0:                            EOF;
sl@0: #else
sl@0:                            std::char_traits<char_type>::eof();
sl@0: #endif
sl@0:             }
sl@0:             bool operator>>(std::string &output)
sl@0:             {
sl@0:                 #if defined(BOOST_NO_STRINGSTREAM)
sl@0:                 stream << '\0';
sl@0:                 #endif
sl@0:                 output = stream.str();
sl@0:                 return true;
sl@0:             }
sl@0:             #ifndef DISABLE_WIDE_CHAR_SUPPORT
sl@0:             bool operator>>(std::wstring &output)
sl@0:             {
sl@0:                 output = stream.str();
sl@0:                 return true;
sl@0:             }
sl@0:             #endif
sl@0:         private:
sl@0:             #if defined(BOOST_NO_STRINGSTREAM)
sl@0:             std::strstream stream;
sl@0:             #elif defined(BOOST_NO_STD_LOCALE)
sl@0:             std::stringstream stream;
sl@0:             #else
sl@0:             std::basic_stringstream<char_type> stream;
sl@0:             #endif
sl@0:         };
sl@0:     }
sl@0: 
sl@0:     #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
sl@0: 
sl@0:     // call-by-const reference version
sl@0: 
sl@0:     namespace detail
sl@0:     {
sl@0:         template<class T>
sl@0:         struct array_to_pointer_decay
sl@0:         {
sl@0:             typedef T type;
sl@0:         };
sl@0: 
sl@0:         template<class T, std::size_t N>
sl@0:         struct array_to_pointer_decay<T[N]>
sl@0:         {
sl@0:             typedef const T * type;
sl@0:         };
sl@0:     }
sl@0: 
sl@0:     template<typename Target, typename Source>
sl@0:     Target lexical_cast(const Source &arg)
sl@0:     {
sl@0:         typedef typename detail::array_to_pointer_decay<Source>::type NewSource;
sl@0: 
sl@0:         detail::lexical_stream<Target, NewSource> interpreter;
sl@0:         Target result ;
sl@0: 
sl@0:         if(!(interpreter << arg && interpreter >> result))
sl@0:             throw_exception(bad_lexical_cast(typeid(NewSource), typeid(Target)));
sl@0:         return result;
sl@0:     }
sl@0: 
sl@0:     #else
sl@0: 
sl@0:     // call-by-value fallback version (deprecated)
sl@0: 
sl@0:     template<typename Target, typename Source>
sl@0:     Target lexical_cast(Source arg)
sl@0:     {
sl@0:         detail::lexical_stream<Target, Source> interpreter;
sl@0:         Target result;
sl@0: 
sl@0:         if(!(interpreter << arg && interpreter >> result))
sl@0:             throw_exception(bad_lexical_cast(typeid(Source), typeid(Target)));
sl@0:         return result;
sl@0:     }
sl@0: 
sl@0:     #endif
sl@0: }
sl@0: 
sl@0: // Copyright Kevlin Henney, 2000-2005. All rights reserved.
sl@0: //
sl@0: // Distributed under the Boost Software License, Version 1.0. (See
sl@0: // accompanying file LICENSE_1_0.txt or copy at
sl@0: // http://www.boost.org/LICENSE_1_0.txt)
sl@0: 
sl@0: #undef DISABLE_WIDE_CHAR_SUPPORT
sl@0: #endif