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lexical_cast.hpp improvements: interpreter was split to input and output streams to reduce size of binaries and improve compilation times, fixed typo from previous commit (refs #9046)

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[SVN r85528]
This commit is contained in:
Antony Polukhin
2013-08-30 14:37:32 +00:00
parent c58a55a512
commit 47041de63a
1 changed files with 67 additions and 25 deletions
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92
include/boost/lexical_cast.hpp
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@ -1285,28 +1285,38 @@ namespace boost {
namespace detail
{
struct do_not_construct_out_stream_t{};
template <class CharT, class Traits>
struct out_stream_helper_trait {
#if defined(BOOST_NO_STRINGSTREAM)
typedef std::ostrstream out_stream_t;
typedef void buffer_t;
#elif defined(BOOST_NO_STD_LOCALE)
typedef std::ostringstream out_stream_t;
typedef basic_unlockedbuf<std::streambuf, char> buffer_t;
#else
typedef std::basic_ostringstream<CharT, Traits>
out_stream_t;
typedef basic_unlockedbuf<std::basic_streambuf<CharT, Traits>, CharT>
buffer_t;
#endif
};
}
namespace detail // optimized stream wrapper
namespace detail // optimized stream wrappers
{
// String representation of Source has an upper limit.
template< class CharT // a result of widest_char transformation
, class Traits // usually char_traits<CharT>
, class Traits
, bool RequiresStringbuffer
, std::size_t CharacterBufferSize
>
class lexical_stream_limited_src
{
class lexical_istream_limited_src {
typedef BOOST_DEDUCED_TYPENAME out_stream_helper_trait<CharT, Traits>::buffer_t
buffer_t;
#if defined(BOOST_NO_STRINGSTREAM)
typedef std::ostrstream out_stream_t;
#elif defined(BOOST_NO_STD_LOCALE)
typedef std::ostringstream out_stream_t;
typedef basic_unlockedbuf<std::streambuf, char> buffer_t;
#else
typedef std::basic_ostringstream<CharT, Traits> out_stream_t;
typedef basic_unlockedbuf<std::basic_streambuf<CharT, Traits>, CharT> buffer_t;
#endif
typedef BOOST_DEDUCED_TYPENAME out_stream_helper_trait<CharT, Traits>::out_stream_t
out_stream_t;
typedef BOOST_DEDUCED_TYPENAME boost::mpl::if_c<
RequiresStringbuffer,
out_stream_t,
@ -1323,15 +1333,23 @@ namespace boost {
const CharT* finish;
public:
lexical_stream_limited_src() BOOST_NOEXCEPT
lexical_istream_limited_src() BOOST_NOEXCEPT
: start(buffer)
, finish(buffer + CharacterBufferSize)
{}
const CharT* cbegin() const BOOST_NOEXCEPT {
return start;
}
const CharT* cend() const BOOST_NOEXCEPT {
return finish;
}
private:
// Undefined:
lexical_stream_limited_src(lexical_stream_limited_src const&);
void operator=(lexical_stream_limited_src const&);
lexical_istream_limited_src(lexical_istream_limited_src const&);
void operator=(lexical_istream_limited_src const&);
/************************************ HELPER FUNCTIONS FOR OPERATORS << ( ... ) ********************************/
bool shl_char(CharT ch) BOOST_NOEXCEPT {
@ -1656,6 +1674,20 @@ namespace boost {
template <class InStreamable>
bool operator<<(const InStreamable& input) { return shl_input_streamable(input); }
};
template <class CharT, class Traits>
class lexical_ostream_limited_src {
//`[start, finish)` is the range to output by `operator >>`
const CharT* start;
const CharT* const finish;
public:
lexical_ostream_limited_src(const CharT* begin, const CharT* end) BOOST_NOEXCEPT
: start(begin)
, finish(end)
{}
/************************************ HELPER FUNCTIONS FOR OPERATORS >> ( ... ) ********************************/
private:
@ -1721,6 +1753,8 @@ namespace boost {
"support such conversions. Try updating it."
);
#endif
typedef BOOST_DEDUCED_TYPENAME out_stream_helper_trait<CharT, Traits>::buffer_t
buffer_t;
#if defined(BOOST_NO_STRINGSTREAM)
std::istrstream stream(start, finish - start);
@ -1846,7 +1880,7 @@ namespace boost {
(sizeof(boost::array<C, N>) == sizeof(boost::array<C, N>)),
"std::array<C, N> and boost::array<C, N> must have exactly the same layout."
);
return ((*this) >> reinterpret_cast<boost::array<C, N>& >(input));
return ((*this) >> reinterpret_cast<boost::array<C, N>& >(output));
}
#endif
@ -2035,20 +2069,28 @@ namespace boost {
{
typedef lexical_cast_stream_traits<Source, Target> stream_trait;
typedef detail::lexical_stream_limited_src<
typedef detail::lexical_istream_limited_src<
BOOST_DEDUCED_TYPENAME stream_trait::char_type,
BOOST_DEDUCED_TYPENAME stream_trait::traits,
stream_trait::requires_stringbuf,
stream_trait::len_t::value + 1
> interpreter_type;
> i_interpreter_type;
typedef detail::lexical_ostream_limited_src<
BOOST_DEDUCED_TYPENAME stream_trait::char_type,
BOOST_DEDUCED_TYPENAME stream_trait::traits
> o_interpreter_type;
// Target type must be default constructible
Target result;
interpreter_type interpreter;
i_interpreter_type i_interpreter;
if (! (i_interpreter.operator <<(arg)))
BOOST_LCAST_THROW_BAD_CAST(Source, Target);
o_interpreter_type out(i_interpreter.cbegin(), i_interpreter.cend());
// Disabling ADL, by directly specifying operators.
if(!(interpreter.operator <<(arg) && interpreter.operator >>(result)))
if(!(out.operator >>(result)))
BOOST_LCAST_THROW_BAD_CAST(Source, Target);
return result;
@ -2227,7 +2269,7 @@ namespace boost {
template <typename Target>
inline Target lexical_cast(const char* chars, std::size_t count)
{
{
return ::boost::lexical_cast<Target>(
::boost::iterator_range<const char*>(chars, chars + count)
);
@ -2240,7 +2282,7 @@ namespace boost {
return ::boost::lexical_cast<Target>(
::boost::iterator_range<const unsigned char*>(chars, chars + count)
);
}
}
template <typename Target>
inline Target lexical_cast(const signed char* chars, std::size_t count)