0,0 → 1,881 |
// Input streams -*- C++ -*- |
|
// Copyright (C) 1997-2013 Free Software Foundation, Inc. |
// |
// This file is part of the GNU ISO C++ Library. This library is free |
// software; you can redistribute it and/or modify it under the |
// terms of the GNU General Public License as published by the |
// Free Software Foundation; either version 3, or (at your option) |
// any later version. |
|
// This library is distributed in the hope that it will be useful, |
// but WITHOUT ANY WARRANTY; without even the implied warranty of |
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
// GNU General Public License for more details. |
|
// Under Section 7 of GPL version 3, you are granted additional |
// permissions described in the GCC Runtime Library Exception, version |
// 3.1, as published by the Free Software Foundation. |
|
// You should have received a copy of the GNU General Public License and |
// a copy of the GCC Runtime Library Exception along with this program; |
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
// <http://www.gnu.org/licenses/>. |
|
// |
// ISO C++ 14882: 27.6.1 Input streams |
// |
|
/** @file include/istream |
* This is a Standard C++ Library header. |
*/ |
|
#ifndef _GLIBCXX_ISTREAM |
#define _GLIBCXX_ISTREAM 1 |
|
#pragma GCC system_header |
|
#include <ios> |
#include <ostream> |
|
namespace std _GLIBCXX_VISIBILITY(default) |
{ |
_GLIBCXX_BEGIN_NAMESPACE_VERSION |
|
/** |
* @brief Template class basic_istream. |
* @ingroup io |
* |
* @tparam _CharT Type of character stream. |
* @tparam _Traits Traits for character type, defaults to |
* char_traits<_CharT>. |
* |
* This is the base class for all input streams. It provides text |
* formatting of all builtin types, and communicates with any class |
* derived from basic_streambuf to do the actual input. |
*/ |
template<typename _CharT, typename _Traits> |
class basic_istream : virtual public basic_ios<_CharT, _Traits> |
{ |
public: |
// Types (inherited from basic_ios (27.4.4)): |
typedef _CharT char_type; |
typedef typename _Traits::int_type int_type; |
typedef typename _Traits::pos_type pos_type; |
typedef typename _Traits::off_type off_type; |
typedef _Traits traits_type; |
|
// Non-standard Types: |
typedef basic_streambuf<_CharT, _Traits> __streambuf_type; |
typedef basic_ios<_CharT, _Traits> __ios_type; |
typedef basic_istream<_CharT, _Traits> __istream_type; |
typedef num_get<_CharT, istreambuf_iterator<_CharT, _Traits> > |
__num_get_type; |
typedef ctype<_CharT> __ctype_type; |
|
protected: |
// Data Members: |
/** |
* The number of characters extracted in the previous unformatted |
* function; see gcount(). |
*/ |
streamsize _M_gcount; |
|
public: |
/** |
* @brief Base constructor. |
* |
* This ctor is almost never called by the user directly, rather from |
* derived classes' initialization lists, which pass a pointer to |
* their own stream buffer. |
*/ |
explicit |
basic_istream(__streambuf_type* __sb) |
: _M_gcount(streamsize(0)) |
{ this->init(__sb); } |
|
/** |
* @brief Base destructor. |
* |
* This does very little apart from providing a virtual base dtor. |
*/ |
virtual |
~basic_istream() |
{ _M_gcount = streamsize(0); } |
|
/// Safe prefix/suffix operations. |
class sentry; |
friend class sentry; |
|
//@{ |
/** |
* @brief Interface for manipulators. |
* |
* Manipulators such as @c std::ws and @c std::dec use these |
* functions in constructs like |
* <code>std::cin >> std::ws</code>. |
* For more information, see the iomanip header. |
*/ |
__istream_type& |
operator>>(__istream_type& (*__pf)(__istream_type&)) |
{ return __pf(*this); } |
|
__istream_type& |
operator>>(__ios_type& (*__pf)(__ios_type&)) |
{ |
__pf(*this); |
return *this; |
} |
|
__istream_type& |
operator>>(ios_base& (*__pf)(ios_base&)) |
{ |
__pf(*this); |
return *this; |
} |
//@} |
|
//@{ |
/** |
* @name Extractors |
* |
* All the @c operator>> functions (aka <em>formatted input |
* functions</em>) have some common behavior. Each starts by |
* constructing a temporary object of type std::basic_istream::sentry |
* with the second argument (noskipws) set to false. This has several |
* effects, concluding with the setting of a status flag; see the |
* sentry documentation for more. |
* |
* If the sentry status is good, the function tries to extract |
* whatever data is appropriate for the type of the argument. |
* |
* If an exception is thrown during extraction, ios_base::badbit |
* will be turned on in the stream's error state without causing an |
* ios_base::failure to be thrown. The original exception will then |
* be rethrown. |
*/ |
|
//@{ |
/** |
* @brief Integer arithmetic extractors |
* @param __n A variable of builtin integral type. |
* @return @c *this if successful |
* |
* These functions use the stream's current locale (specifically, the |
* @c num_get facet) to parse the input data. |
*/ |
__istream_type& |
operator>>(bool& __n) |
{ return _M_extract(__n); } |
|
__istream_type& |
operator>>(short& __n); |
|
__istream_type& |
operator>>(unsigned short& __n) |
{ return _M_extract(__n); } |
|
__istream_type& |
operator>>(int& __n); |
|
__istream_type& |
operator>>(unsigned int& __n) |
{ return _M_extract(__n); } |
|
__istream_type& |
operator>>(long& __n) |
{ return _M_extract(__n); } |
|
__istream_type& |
operator>>(unsigned long& __n) |
{ return _M_extract(__n); } |
|
#ifdef _GLIBCXX_USE_LONG_LONG |
__istream_type& |
operator>>(long long& __n) |
{ return _M_extract(__n); } |
|
__istream_type& |
operator>>(unsigned long long& __n) |
{ return _M_extract(__n); } |
#endif |
//@} |
|
//@{ |
/** |
* @brief Floating point arithmetic extractors |
* @param __f A variable of builtin floating point type. |
* @return @c *this if successful |
* |
* These functions use the stream's current locale (specifically, the |
* @c num_get facet) to parse the input data. |
*/ |
__istream_type& |
operator>>(float& __f) |
{ return _M_extract(__f); } |
|
__istream_type& |
operator>>(double& __f) |
{ return _M_extract(__f); } |
|
__istream_type& |
operator>>(long double& __f) |
{ return _M_extract(__f); } |
//@} |
|
/** |
* @brief Basic arithmetic extractors |
* @param __p A variable of pointer type. |
* @return @c *this if successful |
* |
* These functions use the stream's current locale (specifically, the |
* @c num_get facet) to parse the input data. |
*/ |
__istream_type& |
operator>>(void*& __p) |
{ return _M_extract(__p); } |
|
/** |
* @brief Extracting into another streambuf. |
* @param __sb A pointer to a streambuf |
* |
* This function behaves like one of the basic arithmetic extractors, |
* in that it also constructs a sentry object and has the same error |
* handling behavior. |
* |
* If @p __sb is NULL, the stream will set failbit in its error state. |
* |
* Characters are extracted from this stream and inserted into the |
* @p __sb streambuf until one of the following occurs: |
* |
* - the input stream reaches end-of-file, |
* - insertion into the output buffer fails (in this case, the |
* character that would have been inserted is not extracted), or |
* - an exception occurs (and in this case is caught) |
* |
* If the function inserts no characters, failbit is set. |
*/ |
__istream_type& |
operator>>(__streambuf_type* __sb); |
//@} |
|
// [27.6.1.3] unformatted input |
/** |
* @brief Character counting |
* @return The number of characters extracted by the previous |
* unformatted input function dispatched for this stream. |
*/ |
streamsize |
gcount() const |
{ return _M_gcount; } |
|
//@{ |
/** |
* @name Unformatted Input Functions |
* |
* All the unformatted input functions have some common behavior. |
* Each starts by constructing a temporary object of type |
* std::basic_istream::sentry with the second argument (noskipws) |
* set to true. This has several effects, concluding with the |
* setting of a status flag; see the sentry documentation for more. |
* |
* If the sentry status is good, the function tries to extract |
* whatever data is appropriate for the type of the argument. |
* |
* The number of characters extracted is stored for later retrieval |
* by gcount(). |
* |
* If an exception is thrown during extraction, ios_base::badbit |
* will be turned on in the stream's error state without causing an |
* ios_base::failure to be thrown. The original exception will then |
* be rethrown. |
*/ |
|
/** |
* @brief Simple extraction. |
* @return A character, or eof(). |
* |
* Tries to extract a character. If none are available, sets failbit |
* and returns traits::eof(). |
*/ |
int_type |
get(); |
|
/** |
* @brief Simple extraction. |
* @param __c The character in which to store data. |
* @return *this |
* |
* Tries to extract a character and store it in @a __c. If none are |
* available, sets failbit and returns traits::eof(). |
* |
* @note This function is not overloaded on signed char and |
* unsigned char. |
*/ |
__istream_type& |
get(char_type& __c); |
|
/** |
* @brief Simple multiple-character extraction. |
* @param __s Pointer to an array. |
* @param __n Maximum number of characters to store in @a __s. |
* @param __delim A "stop" character. |
* @return *this |
* |
* Characters are extracted and stored into @a __s until one of the |
* following happens: |
* |
* - @c __n-1 characters are stored |
* - the input sequence reaches EOF |
* - the next character equals @a __delim, in which case the character |
* is not extracted |
* |
* If no characters are stored, failbit is set in the stream's error |
* state. |
* |
* In any case, a null character is stored into the next location in |
* the array. |
* |
* @note This function is not overloaded on signed char and |
* unsigned char. |
*/ |
__istream_type& |
get(char_type* __s, streamsize __n, char_type __delim); |
|
/** |
* @brief Simple multiple-character extraction. |
* @param __s Pointer to an array. |
* @param __n Maximum number of characters to store in @a s. |
* @return *this |
* |
* Returns @c get(__s,__n,widen('\\n')). |
*/ |
__istream_type& |
get(char_type* __s, streamsize __n) |
{ return this->get(__s, __n, this->widen('\n')); } |
|
/** |
* @brief Extraction into another streambuf. |
* @param __sb A streambuf in which to store data. |
* @param __delim A "stop" character. |
* @return *this |
* |
* Characters are extracted and inserted into @a __sb until one of the |
* following happens: |
* |
* - the input sequence reaches EOF |
* - insertion into the output buffer fails (in this case, the |
* character that would have been inserted is not extracted) |
* - the next character equals @a __delim (in this case, the character |
* is not extracted) |
* - an exception occurs (and in this case is caught) |
* |
* If no characters are stored, failbit is set in the stream's error |
* state. |
*/ |
__istream_type& |
get(__streambuf_type& __sb, char_type __delim); |
|
/** |
* @brief Extraction into another streambuf. |
* @param __sb A streambuf in which to store data. |
* @return *this |
* |
* Returns @c get(__sb,widen('\\n')). |
*/ |
__istream_type& |
get(__streambuf_type& __sb) |
{ return this->get(__sb, this->widen('\n')); } |
|
/** |
* @brief String extraction. |
* @param __s A character array in which to store the data. |
* @param __n Maximum number of characters to extract. |
* @param __delim A "stop" character. |
* @return *this |
* |
* Extracts and stores characters into @a __s until one of the |
* following happens. Note that these criteria are required to be |
* tested in the order listed here, to allow an input line to exactly |
* fill the @a __s array without setting failbit. |
* |
* -# the input sequence reaches end-of-file, in which case eofbit |
* is set in the stream error state |
* -# the next character equals @c __delim, in which case the character |
* is extracted (and therefore counted in @c gcount()) but not stored |
* -# @c __n-1 characters are stored, in which case failbit is set |
* in the stream error state |
* |
* If no characters are extracted, failbit is set. (An empty line of |
* input should therefore not cause failbit to be set.) |
* |
* In any case, a null character is stored in the next location in |
* the array. |
*/ |
__istream_type& |
getline(char_type* __s, streamsize __n, char_type __delim); |
|
/** |
* @brief String extraction. |
* @param __s A character array in which to store the data. |
* @param __n Maximum number of characters to extract. |
* @return *this |
* |
* Returns @c getline(__s,__n,widen('\\n')). |
*/ |
__istream_type& |
getline(char_type* __s, streamsize __n) |
{ return this->getline(__s, __n, this->widen('\n')); } |
|
/** |
* @brief Discarding characters |
* @param __n Number of characters to discard. |
* @param __delim A "stop" character. |
* @return *this |
* |
* Extracts characters and throws them away until one of the |
* following happens: |
* - if @a __n @c != @c std::numeric_limits<int>::max(), @a __n |
* characters are extracted |
* - the input sequence reaches end-of-file |
* - the next character equals @a __delim (in this case, the character |
* is extracted); note that this condition will never occur if |
* @a __delim equals @c traits::eof(). |
* |
* NB: Provide three overloads, instead of the single function |
* (with defaults) mandated by the Standard: this leads to a |
* better performing implementation, while still conforming to |
* the Standard. |
*/ |
__istream_type& |
ignore(streamsize __n, int_type __delim); |
|
__istream_type& |
ignore(streamsize __n); |
|
__istream_type& |
ignore(); |
|
/** |
* @brief Looking ahead in the stream |
* @return The next character, or eof(). |
* |
* If, after constructing the sentry object, @c good() is false, |
* returns @c traits::eof(). Otherwise reads but does not extract |
* the next input character. |
*/ |
int_type |
peek(); |
|
/** |
* @brief Extraction without delimiters. |
* @param __s A character array. |
* @param __n Maximum number of characters to store. |
* @return *this |
* |
* If the stream state is @c good(), extracts characters and stores |
* them into @a __s until one of the following happens: |
* - @a __n characters are stored |
* - the input sequence reaches end-of-file, in which case the error |
* state is set to @c failbit|eofbit. |
* |
* @note This function is not overloaded on signed char and |
* unsigned char. |
*/ |
__istream_type& |
read(char_type* __s, streamsize __n); |
|
/** |
* @brief Extraction until the buffer is exhausted, but no more. |
* @param __s A character array. |
* @param __n Maximum number of characters to store. |
* @return The number of characters extracted. |
* |
* Extracts characters and stores them into @a __s depending on the |
* number of characters remaining in the streambuf's buffer, |
* @c rdbuf()->in_avail(), called @c A here: |
* - if @c A @c == @c -1, sets eofbit and extracts no characters |
* - if @c A @c == @c 0, extracts no characters |
* - if @c A @c > @c 0, extracts @c min(A,n) |
* |
* The goal is to empty the current buffer, and to not request any |
* more from the external input sequence controlled by the streambuf. |
*/ |
streamsize |
readsome(char_type* __s, streamsize __n); |
|
/** |
* @brief Unextracting a single character. |
* @param __c The character to push back into the input stream. |
* @return *this |
* |
* If @c rdbuf() is not null, calls @c rdbuf()->sputbackc(c). |
* |
* If @c rdbuf() is null or if @c sputbackc() fails, sets badbit in |
* the error state. |
* |
* @note This function first clears eofbit. Since no characters |
* are extracted, the next call to @c gcount() will return 0, |
* as required by DR 60. |
*/ |
__istream_type& |
putback(char_type __c); |
|
/** |
* @brief Unextracting the previous character. |
* @return *this |
* |
* If @c rdbuf() is not null, calls @c rdbuf()->sungetc(c). |
* |
* If @c rdbuf() is null or if @c sungetc() fails, sets badbit in |
* the error state. |
* |
* @note This function first clears eofbit. Since no characters |
* are extracted, the next call to @c gcount() will return 0, |
* as required by DR 60. |
*/ |
__istream_type& |
unget(); |
|
/** |
* @brief Synchronizing the stream buffer. |
* @return 0 on success, -1 on failure |
* |
* If @c rdbuf() is a null pointer, returns -1. |
* |
* Otherwise, calls @c rdbuf()->pubsync(), and if that returns -1, |
* sets badbit and returns -1. |
* |
* Otherwise, returns 0. |
* |
* @note This function does not count the number of characters |
* extracted, if any, and therefore does not affect the next |
* call to @c gcount(). |
*/ |
int |
sync(); |
|
/** |
* @brief Getting the current read position. |
* @return A file position object. |
* |
* If @c fail() is not false, returns @c pos_type(-1) to indicate |
* failure. Otherwise returns @c rdbuf()->pubseekoff(0,cur,in). |
* |
* @note This function does not count the number of characters |
* extracted, if any, and therefore does not affect the next |
* call to @c gcount(). At variance with putback, unget and |
* seekg, eofbit is not cleared first. |
*/ |
pos_type |
tellg(); |
|
/** |
* @brief Changing the current read position. |
* @param __pos A file position object. |
* @return *this |
* |
* If @c fail() is not true, calls @c rdbuf()->pubseekpos(__pos). If |
* that function fails, sets failbit. |
* |
* @note This function first clears eofbit. It does not count the |
* number of characters extracted, if any, and therefore does |
* not affect the next call to @c gcount(). |
*/ |
__istream_type& |
seekg(pos_type); |
|
/** |
* @brief Changing the current read position. |
* @param __off A file offset object. |
* @param __dir The direction in which to seek. |
* @return *this |
* |
* If @c fail() is not true, calls @c rdbuf()->pubseekoff(__off,__dir). |
* If that function fails, sets failbit. |
* |
* @note This function first clears eofbit. It does not count the |
* number of characters extracted, if any, and therefore does |
* not affect the next call to @c gcount(). |
*/ |
__istream_type& |
seekg(off_type, ios_base::seekdir); |
//@} |
|
protected: |
basic_istream() |
: _M_gcount(streamsize(0)) |
{ this->init(0); } |
|
template<typename _ValueT> |
__istream_type& |
_M_extract(_ValueT& __v); |
}; |
|
/// Explicit specialization declarations, defined in src/istream.cc. |
template<> |
basic_istream<char>& |
basic_istream<char>:: |
getline(char_type* __s, streamsize __n, char_type __delim); |
|
template<> |
basic_istream<char>& |
basic_istream<char>:: |
ignore(streamsize __n); |
|
template<> |
basic_istream<char>& |
basic_istream<char>:: |
ignore(streamsize __n, int_type __delim); |
|
#ifdef _GLIBCXX_USE_WCHAR_T |
template<> |
basic_istream<wchar_t>& |
basic_istream<wchar_t>:: |
getline(char_type* __s, streamsize __n, char_type __delim); |
|
template<> |
basic_istream<wchar_t>& |
basic_istream<wchar_t>:: |
ignore(streamsize __n); |
|
template<> |
basic_istream<wchar_t>& |
basic_istream<wchar_t>:: |
ignore(streamsize __n, int_type __delim); |
#endif |
|
/** |
* @brief Performs setup work for input streams. |
* |
* Objects of this class are created before all of the standard |
* extractors are run. It is responsible for <em>exception-safe |
* prefix and suffix operations,</em> although only prefix actions |
* are currently required by the standard. |
*/ |
template<typename _CharT, typename _Traits> |
class basic_istream<_CharT, _Traits>::sentry |
{ |
// Data Members. |
bool _M_ok; |
|
public: |
/// Easy access to dependent types. |
typedef _Traits traits_type; |
typedef basic_streambuf<_CharT, _Traits> __streambuf_type; |
typedef basic_istream<_CharT, _Traits> __istream_type; |
typedef typename __istream_type::__ctype_type __ctype_type; |
typedef typename _Traits::int_type __int_type; |
|
/** |
* @brief The constructor performs all the work. |
* @param __is The input stream to guard. |
* @param __noskipws Whether to consume whitespace or not. |
* |
* If the stream state is good (@a __is.good() is true), then the |
* following actions are performed, otherwise the sentry state |
* is false (<em>not okay</em>) and failbit is set in the |
* stream state. |
* |
* The sentry's preparatory actions are: |
* |
* -# if the stream is tied to an output stream, @c is.tie()->flush() |
* is called to synchronize the output sequence |
* -# if @a __noskipws is false, and @c ios_base::skipws is set in |
* @c is.flags(), the sentry extracts and discards whitespace |
* characters from the stream. The currently imbued locale is |
* used to determine whether each character is whitespace. |
* |
* If the stream state is still good, then the sentry state becomes |
* true (@a okay). |
*/ |
explicit |
sentry(basic_istream<_CharT, _Traits>& __is, bool __noskipws = false); |
|
/** |
* @brief Quick status checking. |
* @return The sentry state. |
* |
* For ease of use, sentries may be converted to booleans. The |
* return value is that of the sentry state (true == okay). |
*/ |
#if __cplusplus >= 201103L |
explicit |
#endif |
operator bool() const |
{ return _M_ok; } |
}; |
|
//@{ |
/** |
* @brief Character extractors |
* @param __in An input stream. |
* @param __c A character reference. |
* @return in |
* |
* Behaves like one of the formatted arithmetic extractors described in |
* std::basic_istream. After constructing a sentry object with good |
* status, this function extracts a character (if one is available) and |
* stores it in @a __c. Otherwise, sets failbit in the input stream. |
*/ |
template<typename _CharT, typename _Traits> |
basic_istream<_CharT, _Traits>& |
operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c); |
|
template<class _Traits> |
inline basic_istream<char, _Traits>& |
operator>>(basic_istream<char, _Traits>& __in, unsigned char& __c) |
{ return (__in >> reinterpret_cast<char&>(__c)); } |
|
template<class _Traits> |
inline basic_istream<char, _Traits>& |
operator>>(basic_istream<char, _Traits>& __in, signed char& __c) |
{ return (__in >> reinterpret_cast<char&>(__c)); } |
//@} |
|
//@{ |
/** |
* @brief Character string extractors |
* @param __in An input stream. |
* @param __s A pointer to a character array. |
* @return __in |
* |
* Behaves like one of the formatted arithmetic extractors described in |
* std::basic_istream. After constructing a sentry object with good |
* status, this function extracts up to @c n characters and stores them |
* into the array starting at @a __s. @c n is defined as: |
* |
* - if @c width() is greater than zero, @c n is width() otherwise |
* - @c n is <em>the number of elements of the largest array of * |
* - @c char_type that can store a terminating @c eos.</em> |
* - [27.6.1.2.3]/6 |
* |
* Characters are extracted and stored until one of the following happens: |
* - @c n-1 characters are stored |
* - EOF is reached |
* - the next character is whitespace according to the current locale |
* - the next character is a null byte (i.e., @c charT() ) |
* |
* @c width(0) is then called for the input stream. |
* |
* If no characters are extracted, sets failbit. |
*/ |
template<typename _CharT, typename _Traits> |
basic_istream<_CharT, _Traits>& |
operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s); |
|
// Explicit specialization declaration, defined in src/istream.cc. |
template<> |
basic_istream<char>& |
operator>>(basic_istream<char>& __in, char* __s); |
|
template<class _Traits> |
inline basic_istream<char, _Traits>& |
operator>>(basic_istream<char, _Traits>& __in, unsigned char* __s) |
{ return (__in >> reinterpret_cast<char*>(__s)); } |
|
template<class _Traits> |
inline basic_istream<char, _Traits>& |
operator>>(basic_istream<char, _Traits>& __in, signed char* __s) |
{ return (__in >> reinterpret_cast<char*>(__s)); } |
//@} |
|
/** |
* @brief Template class basic_iostream |
* @ingroup io |
* |
* @tparam _CharT Type of character stream. |
* @tparam _Traits Traits for character type, defaults to |
* char_traits<_CharT>. |
* |
* This class multiply inherits from the input and output stream classes |
* simply to provide a single interface. |
*/ |
template<typename _CharT, typename _Traits> |
class basic_iostream |
: public basic_istream<_CharT, _Traits>, |
public basic_ostream<_CharT, _Traits> |
{ |
public: |
// _GLIBCXX_RESOLVE_LIB_DEFECTS |
// 271. basic_iostream missing typedefs |
// Types (inherited): |
typedef _CharT char_type; |
typedef typename _Traits::int_type int_type; |
typedef typename _Traits::pos_type pos_type; |
typedef typename _Traits::off_type off_type; |
typedef _Traits traits_type; |
|
// Non-standard Types: |
typedef basic_istream<_CharT, _Traits> __istream_type; |
typedef basic_ostream<_CharT, _Traits> __ostream_type; |
|
/** |
* @brief Constructor does nothing. |
* |
* Both of the parent classes are initialized with the same |
* streambuf pointer passed to this constructor. |
*/ |
explicit |
basic_iostream(basic_streambuf<_CharT, _Traits>* __sb) |
: __istream_type(__sb), __ostream_type(__sb) { } |
|
/** |
* @brief Destructor does nothing. |
*/ |
virtual |
~basic_iostream() { } |
|
protected: |
basic_iostream() |
: __istream_type(), __ostream_type() { } |
}; |
|
/** |
* @brief Quick and easy way to eat whitespace |
* |
* This manipulator extracts whitespace characters, stopping when the |
* next character is non-whitespace, or when the input sequence is empty. |
* If the sequence is empty, @c eofbit is set in the stream, but not |
* @c failbit. |
* |
* The current locale is used to distinguish whitespace characters. |
* |
* Example: |
* @code |
* MyClass mc; |
* |
* std::cin >> std::ws >> mc; |
* @endcode |
* will skip leading whitespace before calling operator>> on cin and your |
* object. Note that the same effect can be achieved by creating a |
* std::basic_istream::sentry inside your definition of operator>>. |
*/ |
template<typename _CharT, typename _Traits> |
basic_istream<_CharT, _Traits>& |
ws(basic_istream<_CharT, _Traits>& __is); |
|
#if __cplusplus >= 201103L |
// [27.7.1.6] Rvalue stream extraction |
/** |
* @brief Generic extractor for rvalue stream |
* @param __is An input stream. |
* @param __x A reference to the extraction target. |
* @return is |
* |
* This is just a forwarding function to allow extraction from |
* rvalue streams since they won't bind to the extractor functions |
* that take an lvalue reference. |
*/ |
template<typename _CharT, typename _Traits, typename _Tp> |
inline basic_istream<_CharT, _Traits>& |
operator>>(basic_istream<_CharT, _Traits>&& __is, _Tp& __x) |
{ return (__is >> __x); } |
#endif // C++11 |
|
_GLIBCXX_END_NAMESPACE_VERSION |
} // namespace |
|
#include <bits/istream.tcc> |
|
#endif /* _GLIBCXX_ISTREAM */ |