lyx_mirror/boost/boost/lexical_cast.hpp
Peter Kümmel c2f99181e6 update boost to version 1.36
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@26648 a592a061-630c-0410-9148-cb99ea01b6c8
2008-09-30 18:01:03 +00:00

1206 lines
38 KiB
C++

#ifndef BOOST_LEXICAL_CAST_INCLUDED
#define BOOST_LEXICAL_CAST_INCLUDED
// Boost lexical_cast.hpp header -------------------------------------------//
//
// See http://www.boost.org/libs/conversion for documentation.
// See end of this header for rights and permissions.
//
// what: lexical_cast custom keyword cast
// who: contributed by Kevlin Henney,
// enhanced with contributions from Terje Slettebo,
// with additional fixes and suggestions from Gennaro Prota,
// Beman Dawes, Dave Abrahams, Daryle Walker, Peter Dimov,
// Alexander Nasonov and other Boosters
// when: November 2000, March 2003, June 2005, June 2006
#include <climits>
#include <cstddef>
#include <istream>
#include <locale>
#include <string>
#include <typeinfo>
#include <boost/config.hpp>
#include <boost/limits.hpp>
#include <boost/mpl/if.hpp>
#include <boost/throw_exception.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/call_traits.hpp>
#include <boost/static_assert.hpp>
#include <boost/detail/lcast_precision.hpp>
#ifdef BOOST_NO_STRINGSTREAM
#include <strstream>
#else
#include <sstream>
#endif
#if defined(BOOST_NO_STRINGSTREAM) || \
defined(BOOST_NO_STD_WSTRING) || \
defined(BOOST_NO_STD_LOCALE)
#define DISABLE_WIDE_CHAR_SUPPORT
#endif
namespace boost
{
// exception used to indicate runtime lexical_cast failure
class bad_lexical_cast : public std::bad_cast
{
public:
bad_lexical_cast() :
source(&typeid(void)), target(&typeid(void))
{
}
bad_lexical_cast(
const std::type_info &source_type_arg,
const std::type_info &target_type_arg) :
source(&source_type_arg), target(&target_type_arg)
{
}
const std::type_info &source_type() const
{
return *source;
}
const std::type_info &target_type() const
{
return *target;
}
virtual const char *what() const throw()
{
return "bad lexical cast: "
"source type value could not be interpreted as target";
}
virtual ~bad_lexical_cast() throw()
{
}
private:
const std::type_info *source;
const std::type_info *target;
};
namespace detail // selectors for choosing stream character type
{
template<typename Type>
struct stream_char
{
typedef char type;
};
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<class CharT, class Traits, class Alloc>
struct stream_char< std::basic_string<CharT,Traits,Alloc> >
{
typedef CharT type;
};
#endif
#ifndef DISABLE_WIDE_CHAR_SUPPORT
#ifndef BOOST_NO_INTRINSIC_WCHAR_T
template<>
struct stream_char<wchar_t>
{
typedef wchar_t type;
};
#endif
template<>
struct stream_char<wchar_t *>
{
typedef wchar_t type;
};
template<>
struct stream_char<const wchar_t *>
{
typedef wchar_t type;
};
#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<>
struct stream_char<std::wstring>
{
typedef wchar_t type;
};
#endif
#endif
template<typename TargetChar, typename SourceChar>
struct widest_char
{
typedef TargetChar type;
};
template<>
struct widest_char<char, wchar_t>
{
typedef wchar_t type;
};
}
namespace detail // deduce_char_traits template
{
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<class CharT, class Target, class Source>
struct deduce_char_traits
{
typedef std::char_traits<CharT> type;
};
template<class CharT, class Traits, class Alloc, class Source>
struct deduce_char_traits< CharT
, std::basic_string<CharT,Traits,Alloc>
, Source
>
{
typedef Traits type;
};
template<class CharT, class Target, class Traits, class Alloc>
struct deduce_char_traits< CharT
, Target
, std::basic_string<CharT,Traits,Alloc>
>
{
typedef Traits type;
};
template<class CharT, class Traits, class Alloc1, class Alloc2>
struct deduce_char_traits< CharT
, std::basic_string<CharT,Traits,Alloc1>
, std::basic_string<CharT,Traits,Alloc2>
>
{
typedef Traits type;
};
#endif
}
namespace detail // lcast_src_length
{
// Return max. length of string representation of Source;
// 0 if unlimited (with exceptions for some types, see below).
// Values with limited string representation are placed to
// the buffer locally defined in lexical_cast function.
// 1 is returned for few types such as CharT const* or
// std::basic_string<CharT> that already have an internal
// buffer ready to be reused by lexical_stream_limited_src.
// Each specialization should have a correspondent operator<<
// defined in lexical_stream_limited_src.
template< class CharT // A result of widest_char transformation.
, class Source // Source type of lexical_cast.
>
struct lcast_src_length
{
BOOST_STATIC_CONSTANT(std::size_t, value = 0);
// To check coverage, build the test with
// bjam --v2 profile optimization=off
static void check_coverage() {}
};
template<>
struct lcast_src_length<char, bool>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
template<>
struct lcast_src_length<char, char>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
// No specializations for:
// lcast_src_length<char, signed char>
// lcast_src_length<char, unsigned char>
// lcast_src_length<char, signed char*>
// lcast_src_length<char, unsigned char*>
// lcast_src_length<char, signed char const*>
// lcast_src_length<char, unsigned char const*>
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<>
struct lcast_src_length<wchar_t, bool>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
template<>
struct lcast_src_length<wchar_t, char>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#ifndef BOOST_NO_INTRINSIC_WCHAR_T
template<>
struct lcast_src_length<wchar_t, wchar_t>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#endif
#endif
template<>
struct lcast_src_length<char, char const*>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
template<>
struct lcast_src_length<char, char*>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<>
struct lcast_src_length<wchar_t, wchar_t const*>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
template<>
struct lcast_src_length<wchar_t, wchar_t*>
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#endif
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<class CharT, class Traits, class Alloc>
struct lcast_src_length< CharT, std::basic_string<CharT,Traits,Alloc> >
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#else
template<>
struct lcast_src_length< char, std::basic_string<char> >
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<>
struct lcast_src_length< wchar_t, std::basic_string<wchar_t> >
{
BOOST_STATIC_CONSTANT(std::size_t, value = 1);
static void check_coverage() {}
};
#endif
#endif
// Helper for integral types.
// Notes on length calculation:
// Max length for 32bit int with grouping "\1" and thousands_sep ',':
// "-2,1,4,7,4,8,3,6,4,7"
// ^ - is_signed
// ^ - 1 digit not counted by digits10
// ^^^^^^^^^^^^^^^^^^ - digits10 * 2
//
// Constant is_specialized is used instead of constant 1
// to prevent buffer overflow in a rare case when
// <boost/limits.hpp> doesn't add missing specialization for
// numeric_limits<T> for some integral type T.
// When is_specialized is false, the whole expression is 0.
template<class Source>
struct lcast_src_length_integral
{
#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
BOOST_STATIC_CONSTANT(std::size_t, value =
std::numeric_limits<Source>::is_signed +
std::numeric_limits<Source>::is_specialized + // == 1
std::numeric_limits<Source>::digits10 * 2
);
#else
BOOST_STATIC_CONSTANT(std::size_t, value = 156);
BOOST_STATIC_ASSERT(sizeof(Source) * CHAR_BIT <= 256);
#endif
};
#define BOOST_AUX_LEXICAL_CAST_DEF1(CharT, T) template<> \
struct lcast_src_length<CharT, T> : lcast_src_length_integral<T> \
{ static void check_coverage() {} };
#ifdef DISABLE_WIDE_CHAR_SUPPORT
#define BOOST_AUX_LEXICAL_CAST_DEF(T) BOOST_AUX_LEXICAL_CAST_DEF1(char, T)
#else
#define BOOST_AUX_LEXICAL_CAST_DEF(T) \
BOOST_AUX_LEXICAL_CAST_DEF1(char, T) \
BOOST_AUX_LEXICAL_CAST_DEF1(wchar_t, T)
#endif
BOOST_AUX_LEXICAL_CAST_DEF(short)
BOOST_AUX_LEXICAL_CAST_DEF(unsigned short)
BOOST_AUX_LEXICAL_CAST_DEF(int)
BOOST_AUX_LEXICAL_CAST_DEF(unsigned int)
BOOST_AUX_LEXICAL_CAST_DEF(long)
BOOST_AUX_LEXICAL_CAST_DEF(unsigned long)
#if defined(BOOST_HAS_LONG_LONG)
BOOST_AUX_LEXICAL_CAST_DEF(boost::ulong_long_type)
BOOST_AUX_LEXICAL_CAST_DEF(boost::long_long_type )
#elif defined(BOOST_HAS_MS_INT64)
BOOST_AUX_LEXICAL_CAST_DEF(unsigned __int64)
BOOST_AUX_LEXICAL_CAST_DEF( __int64)
#endif
#undef BOOST_AUX_LEXICAL_CAST_DEF
#undef BOOST_AUX_LEXICAL_CAST_DEF1
#ifndef BOOST_LCAST_NO_COMPILE_TIME_PRECISION
// Helper for floating point types.
// -1.23456789e-123456
// ^ sign
// ^ leading digit
// ^ decimal point
// ^^^^^^^^ lcast_precision<Source>::value
// ^ "e"
// ^ exponent sign
// ^^^^^^ exponent (assumed 6 or less digits)
// sign + leading digit + decimal point + "e" + exponent sign == 5
template<class Source>
struct lcast_src_length_floating
{
BOOST_STATIC_ASSERT(
std::numeric_limits<Source>::max_exponent10 <= 999999L &&
std::numeric_limits<Source>::min_exponent10 >= -999999L
);
BOOST_STATIC_CONSTANT(std::size_t, value =
5 + lcast_precision<Source>::value + 6
);
};
template<>
struct lcast_src_length<char,float>
: lcast_src_length_floating<float>
{
static void check_coverage() {}
};
template<>
struct lcast_src_length<char,double>
: lcast_src_length_floating<double>
{
static void check_coverage() {}
};
template<>
struct lcast_src_length<char,long double>
: lcast_src_length_floating<long double>
{
static void check_coverage() {}
};
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<>
struct lcast_src_length<wchar_t,float>
: lcast_src_length_floating<float>
{
static void check_coverage() {}
};
template<>
struct lcast_src_length<wchar_t,double>
: lcast_src_length_floating<double>
{
static void check_coverage() {}
};
template<>
struct lcast_src_length<wchar_t,long double>
: lcast_src_length_floating<long double>
{
static void check_coverage() {}
};
#endif // #ifndef DISABLE_WIDE_CHAR_SUPPORT
#endif // #ifndef BOOST_LCAST_NO_COMPILE_TIME_PRECISION
}
namespace detail // '0' and '-' constants
{
template<typename CharT> struct lcast_char_constants;
template<>
struct lcast_char_constants<char>
{
BOOST_STATIC_CONSTANT(char, zero = '0');
BOOST_STATIC_CONSTANT(char, minus = '-');
};
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<>
struct lcast_char_constants<wchar_t>
{
BOOST_STATIC_CONSTANT(wchar_t, zero = L'0');
BOOST_STATIC_CONSTANT(wchar_t, minus = L'-');
};
#endif
}
namespace detail // lexical_streambuf_fake
{
struct lexical_streambuf_fake
{
};
}
namespace detail // lcast_to_unsigned
{
#if (defined _MSC_VER)
# pragma warning( push )
// C4146: unary minus operator applied to unsigned type, result still unsigned
# pragma warning( disable : 4146 )
#endif
inline unsigned int lcast_to_unsigned(int value)
{
unsigned int uval = value;
return value < 0 ? -uval : uval;
}
inline unsigned long lcast_to_unsigned(long value)
{
unsigned long uval = value;
return value < 0 ? -uval : uval;
}
#if defined(BOOST_HAS_LONG_LONG)
inline boost::ulong_long_type lcast_to_unsigned(boost::long_long_type v)
{
boost::ulong_long_type uval = v;
return v < 0 ? -uval : uval;
}
#elif defined(BOOST_HAS_MS_INT64)
inline unsigned __int64 lcast_to_unsigned(__int64 value)
{
unsigned __int64 uval = value;
return value < 0 ? -uval : uval;
}
#endif
#if (defined _MSC_VER)
# pragma warning( pop ) // C4146: unary minus operator applied to unsigned type,
// result still unsigned
#endif
}
namespace detail // lcast_put_unsigned
{
template<class Traits, class T, class CharT>
CharT* lcast_put_unsigned(T n, CharT* finish)
{
#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
BOOST_STATIC_ASSERT(!std::numeric_limits<T>::is_signed);
#endif
CharT thousands_sep = 0;
#ifdef BOOST_LEXICAL_CAST_ASSUME_C_LOCALE
char const* grouping = "";
std::size_t const grouping_size = 0;
#else
std::locale loc;
typedef std::numpunct<CharT> numpunct;
numpunct const& np = BOOST_USE_FACET(numpunct, loc);
std::string const& grouping = np.grouping();
std::string::size_type const grouping_size = grouping.size();
if(grouping_size)
thousands_sep = np.thousands_sep();
#endif
std::string::size_type group = 0; // current group number
char last_grp_size = grouping[0] <= 0 ? CHAR_MAX : grouping[0];
// a) Since grouping is const, grouping[grouping.size()] returns 0.
// b) It's safe to assume here and below that CHAR_MAX
// is equivalent to unlimited grouping:
#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
BOOST_STATIC_ASSERT(std::numeric_limits<T>::digits10 < CHAR_MAX);
#endif
typedef typename Traits::int_type int_type;
CharT const czero = lcast_char_constants<CharT>::zero;
int_type const zero = Traits::to_int_type(czero);
char left = last_grp_size;
do
{
if(left == 0)
{
++group;
if(group < grouping_size)
{
char const grp_size = grouping[group];
last_grp_size = grp_size <= 0 ? CHAR_MAX : grp_size;
}
left = last_grp_size;
--finish;
Traits::assign(*finish, thousands_sep);
}
--left;
--finish;
int_type const digit = static_cast<int_type>(n % 10U);
Traits::assign(*finish, Traits::to_char_type(zero + digit));
n /= 10;
} while(n);
return finish;
}
}
namespace detail // stream wrapper for handling lexical conversions
{
template<typename Target, typename Source, typename Traits>
class lexical_stream
{
private:
typedef typename widest_char<
typename stream_char<Target>::type,
typename stream_char<Source>::type>::type char_type;
typedef Traits traits_type;
public:
lexical_stream(char_type* = 0, char_type* = 0)
{
stream.unsetf(std::ios::skipws);
lcast_set_precision(stream, (Source*)0, (Target*)0);
}
~lexical_stream()
{
#if defined(BOOST_NO_STRINGSTREAM)
stream.freeze(false);
#endif
}
bool operator<<(const Source &input)
{
return !(stream << input).fail();
}
template<typename InputStreamable>
bool operator>>(InputStreamable &output)
{
return !is_pointer<InputStreamable>::value &&
stream >> output &&
stream.get() ==
#if defined(__GNUC__) && (__GNUC__<3) && defined(BOOST_NO_STD_WSTRING)
// GCC 2.9x lacks std::char_traits<>::eof().
// We use BOOST_NO_STD_WSTRING to filter out STLport and libstdc++-v3
// configurations, which do provide std::char_traits<>::eof().
EOF;
#else
traits_type::eof();
#endif
}
#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
bool operator>>(std::string &output)
{
#if defined(BOOST_NO_STRINGSTREAM)
stream << '\0';
#endif
stream.str().swap(output);
return true;
}
#ifndef DISABLE_WIDE_CHAR_SUPPORT
bool operator>>(std::wstring &output)
{
stream.str().swap(output);
return true;
}
#endif
#else
bool operator>>(std::basic_string<char_type,traits_type>& output)
{
stream.str().swap(output);
return true;
}
template<class Alloc>
bool operator>>(std::basic_string<char_type,traits_type,Alloc>& out)
{
std::basic_string<char_type,traits_type> str(stream.str());
out.assign(str.begin(), str.end());
return true;
}
#endif
private:
#if defined(BOOST_NO_STRINGSTREAM)
std::strstream stream;
#elif defined(BOOST_NO_STD_LOCALE)
std::stringstream stream;
#else
std::basic_stringstream<char_type,traits_type> stream;
#endif
};
}
namespace detail // optimized stream wrapper
{
// String representation of Source has an upper limit.
template< class CharT // a result of widest_char transformation
, class Base // lexical_streambuf_fake or basic_streambuf<CharT>
, class Traits // usually char_traits<CharT>
>
class lexical_stream_limited_src : public Base
{
// A string representation of Source is written to [start, finish).
// Currently, it is assumed that [start, finish) is big enough
// to hold a string representation of any Source value.
CharT* start;
CharT* finish;
private:
static void widen_and_assign(char*p, char ch)
{
Traits::assign(*p, ch);
}
#ifndef DISABLE_WIDE_CHAR_SUPPORT
static void widen_and_assign(wchar_t* p, char ch)
{
std::locale loc;
wchar_t w = BOOST_USE_FACET(std::ctype<wchar_t>, loc).widen(ch);
Traits::assign(*p, w);
}
static void widen_and_assign(wchar_t* p, wchar_t ch)
{
Traits::assign(*p, ch);
}
static void widen_and_assign(char*, wchar_t ch); // undefined
#endif
template<class OutputStreamable>
bool lcast_put(const OutputStreamable& input)
{
this->setp(start, finish);
std::basic_ostream<CharT> stream(static_cast<Base*>(this));
lcast_set_precision(stream, (OutputStreamable*)0);
bool const result = !(stream << input).fail();
finish = this->pptr();
return result;
}
// Undefined:
lexical_stream_limited_src(lexical_stream_limited_src const&);
void operator=(lexical_stream_limited_src const&);
public:
lexical_stream_limited_src(CharT* start, CharT* finish)
: start(start)
, finish(finish)
{}
public: // output
template<class Alloc>
bool operator<<(std::basic_string<CharT,Traits,Alloc> const& str)
{
start = const_cast<CharT*>(str.data());
finish = start + str.length();
return true;
}
bool operator<<(bool);
bool operator<<(char);
#if !defined(DISABLE_WIDE_CHAR_SUPPORT) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
bool operator<<(wchar_t);
#endif
bool operator<<(CharT const*);
bool operator<<(short);
bool operator<<(int);
bool operator<<(long);
bool operator<<(unsigned short);
bool operator<<(unsigned int);
bool operator<<(unsigned long);
#if defined(BOOST_HAS_LONG_LONG)
bool operator<<(boost::ulong_long_type);
bool operator<<(boost::long_long_type );
#elif defined(BOOST_HAS_MS_INT64)
bool operator<<(unsigned __int64);
bool operator<<( __int64);
#endif
// These three operators use ostream and streambuf.
// lcast_streambuf_for_source<T>::value is true.
bool operator<<(float);
bool operator<<(double);
bool operator<<(long double);
public: // input
// Generic istream-based algorithm.
// lcast_streambuf_for_target<InputStreamable>::value is true.
template<typename InputStreamable>
bool operator>>(InputStreamable& output)
{
#if (defined _MSC_VER)
# pragma warning( push )
// conditional expression is constant
# pragma warning( disable : 4127 )
#endif
if(is_pointer<InputStreamable>::value)
return false;
this->setg(start, start, finish);
std::basic_istream<CharT> stream(static_cast<Base*>(this));
stream.unsetf(std::ios::skipws);
lcast_set_precision(stream, (InputStreamable*)0);
#if (defined _MSC_VER)
# pragma warning( pop )
#endif
return stream >> output &&
stream.get() ==
#if defined(__GNUC__) && (__GNUC__<3) && defined(BOOST_NO_STD_WSTRING)
// GCC 2.9x lacks std::char_traits<>::eof().
// We use BOOST_NO_STD_WSTRING to filter out STLport and libstdc++-v3
// configurations, which do provide std::char_traits<>::eof().
EOF;
#else
Traits::eof();
#endif
}
bool operator>>(CharT&);
#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
// This #if is in sync with lcast_streambuf_for_target
bool operator>>(std::string&);
#ifndef DISABLE_WIDE_CHAR_SUPPORT
bool operator>>(std::wstring&);
#endif
#else
template<class Alloc>
bool operator>>(std::basic_string<CharT,Traits,Alloc>& str)
{
str.assign(start, finish);
return true;
}
#endif
};
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
bool value)
{
typedef typename Traits::int_type int_type;
CharT const czero = lcast_char_constants<CharT>::zero;
int_type const zero = Traits::to_int_type(czero);
Traits::assign(*start, Traits::to_char_type(zero + value));
finish = start + 1;
return true;
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
char ch)
{
widen_and_assign(start, ch);
finish = start + 1;
return true;
}
#if !defined(DISABLE_WIDE_CHAR_SUPPORT) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
wchar_t ch)
{
widen_and_assign(start, ch);
finish = start + 1;
return true;
}
#endif
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
short n)
{
start = lcast_put_unsigned<Traits>(lcast_to_unsigned(n), finish);
if(n < 0)
{
--start;
CharT const minus = lcast_char_constants<CharT>::minus;
Traits::assign(*start, minus);
}
return true;
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
int n)
{
start = lcast_put_unsigned<Traits>(lcast_to_unsigned(n), finish);
if(n < 0)
{
--start;
CharT const minus = lcast_char_constants<CharT>::minus;
Traits::assign(*start, minus);
}
return true;
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
long n)
{
start = lcast_put_unsigned<Traits>(lcast_to_unsigned(n), finish);
if(n < 0)
{
--start;
CharT const minus = lcast_char_constants<CharT>::minus;
Traits::assign(*start, minus);
}
return true;
}
#if defined(BOOST_HAS_LONG_LONG)
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
boost::long_long_type n)
{
start = lcast_put_unsigned<Traits>(lcast_to_unsigned(n), finish);
if(n < 0)
{
--start;
CharT const minus = lcast_char_constants<CharT>::minus;
Traits::assign(*start, minus);
}
return true;
}
#elif defined(BOOST_HAS_MS_INT64)
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
__int64 n)
{
start = lcast_put_unsigned<Traits>(lcast_to_unsigned(n), finish);
if(n < 0)
{
--start;
CharT const minus = lcast_char_constants<CharT>::minus;
Traits::assign(*start, minus);
}
return true;
}
#endif
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
unsigned short n)
{
start = lcast_put_unsigned<Traits>(lcast_to_unsigned(n), finish);
return true;
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
unsigned int n)
{
start = lcast_put_unsigned<Traits>(n, finish);
return true;
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
unsigned long n)
{
start = lcast_put_unsigned<Traits>(n, finish);
return true;
}
#if defined(BOOST_HAS_LONG_LONG)
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
boost::ulong_long_type n)
{
start = lcast_put_unsigned<Traits>(n, finish);
return true;
}
#elif defined(BOOST_HAS_MS_INT64)
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
unsigned __int64 n)
{
start = lcast_put_unsigned<Traits>(n, finish);
return true;
}
#endif
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
float val)
{
return this->lcast_put(val);
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
double val)
{
return this->lcast_put(val);
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
long double val)
{
return this->lcast_put(val);
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator<<(
CharT const* str)
{
start = const_cast<CharT*>(str);
finish = start + Traits::length(str);
return true;
}
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator>>(
CharT& output)
{
bool const ok = (finish - start == 1);
if(ok)
Traits::assign(output, *start);
return ok;
}
#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator>>(
std::string& str)
{
str.assign(start, finish);
return true;
}
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<typename CharT, class Base, class Traits>
inline bool lexical_stream_limited_src<CharT,Base,Traits>::operator>>(
std::wstring& str)
{
str.assign(start, finish);
return true;
}
#endif
#endif
}
namespace detail // lcast_streambuf_for_source
{
// Returns true if optimized stream wrapper needs ostream for writing.
template<class Source>
struct lcast_streambuf_for_source
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
template<>
struct lcast_streambuf_for_source<float>
{
BOOST_STATIC_CONSTANT(bool, value = true);
};
template<>
struct lcast_streambuf_for_source<double>
{
BOOST_STATIC_CONSTANT(bool, value = true);
};
template<>
struct lcast_streambuf_for_source<long double>
{
BOOST_STATIC_CONSTANT(bool, value = true);
};
}
namespace detail // lcast_streambuf_for_target
{
// Returns true if optimized stream wrapper needs istream for reading.
template<class Target>
struct lcast_streambuf_for_target
{
BOOST_STATIC_CONSTANT(bool, value = true);
};
template<>
struct lcast_streambuf_for_target<char>
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#if !defined(DISABLE_WIDE_CHAR_SUPPORT) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
template<>
struct lcast_streambuf_for_target<wchar_t>
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#endif
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<class Traits, class Alloc>
struct lcast_streambuf_for_target<
std::basic_string<char,Traits,Alloc> >
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<class Traits, class Alloc>
struct lcast_streambuf_for_target<
std::basic_string<wchar_t,Traits,Alloc> >
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#endif
#else
template<>
struct lcast_streambuf_for_target<std::string>
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#ifndef DISABLE_WIDE_CHAR_SUPPORT
template<>
struct lcast_streambuf_for_target<std::wstring>
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#endif
#endif
}
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
// call-by-const reference version
namespace detail
{
template<class T>
struct array_to_pointer_decay
{
typedef T type;
};
template<class T, std::size_t N>
struct array_to_pointer_decay<T[N]>
{
typedef const T * type;
};
template< typename Target
, typename Source
, bool Unlimited // string representation of Source is unlimited
, typename CharT
>
Target lexical_cast(
BOOST_DEDUCED_TYPENAME boost::call_traits<Source>::param_type arg,
CharT* buf, std::size_t src_len)
{
typedef BOOST_DEDUCED_TYPENAME
deduce_char_traits<CharT,Target,Source>::type traits;
typedef BOOST_DEDUCED_TYPENAME boost::mpl::if_c<
lcast_streambuf_for_target<Target>::value ||
lcast_streambuf_for_source<Source>::value
, std::basic_streambuf<CharT>
, lexical_streambuf_fake
>::type base;
BOOST_DEDUCED_TYPENAME boost::mpl::if_c<
Unlimited
, detail::lexical_stream<Target,Source,traits>
, detail::lexical_stream_limited_src<CharT,base,traits>
>::type interpreter(buf, buf + src_len);
// The original form, reproduced below, is more elegant
// but yields a spurious C4701 warning ("possible use of
// "result" before initialization") with VC7.1 (/W4).
//
// Target result;
//
// if(!(interpreter << arg && interpreter >> result))
// throw_exception(bad_lexical_cast(typeid(Source), typeid(Target)));
// return result;
if(interpreter << arg) {
Target result;
if (interpreter >> result)
return result;
}
throw_exception(bad_lexical_cast(typeid(Source), typeid(Target)));
return Target(); // normally never reached (throw_exception)
}
}
template<typename Target, typename Source>
inline Target lexical_cast(const Source &arg)
{
typedef typename detail::array_to_pointer_decay<Source>::type src;
typedef typename detail::widest_char<
typename detail::stream_char<Target>::type
, typename detail::stream_char<src>::type
>::type char_type;
typedef detail::lcast_src_length<char_type, src> lcast_src_length;
std::size_t const src_len = lcast_src_length::value;
char_type buf[src_len + 1];
lcast_src_length::check_coverage();
return detail::lexical_cast<Target, src, !src_len>(arg, buf, src_len);
}
#else
// call-by-value fallback version (deprecated)
template<typename Target, typename Source>
Target lexical_cast(Source arg)
{
typedef typename detail::widest_char<
BOOST_DEDUCED_TYPENAME detail::stream_char<Target>::type
, BOOST_DEDUCED_TYPENAME detail::stream_char<Source>::type
>::type char_type;
typedef std::char_traits<char_type> traits;
detail::lexical_stream<Target, Source, traits> interpreter;
Target result;
if(!(interpreter << arg && interpreter >> result))
throw_exception(bad_lexical_cast(typeid(Source), typeid(Target)));
return result;
}
#endif
}
// Copyright Kevlin Henney, 2000-2005.
// Copyright Alexander Nasonov, 2006-2007.
//
// Distributed under 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)
#undef DISABLE_WIDE_CHAR_SUPPORT
#endif