libstdc++
iomanip
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1 // Standard stream manipulators -*- C++ -*-
2 
3 // Copyright (C) 1997-2014 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file include/iomanip
26  * This is a Standard C++ Library header.
27  */
28 
29 //
30 // ISO C++ 14882: 27.6.3 Standard manipulators
31 //
32 
33 #ifndef _GLIBCXX_IOMANIP
34 #define _GLIBCXX_IOMANIP 1
35 
36 #pragma GCC system_header
37 
38 #include <bits/c++config.h>
39 #include <iosfwd>
40 #include <bits/ios_base.h>
41 
42 #if __cplusplus >= 201103L
43 #include <locale>
44 #endif
45 
46 namespace std _GLIBCXX_VISIBILITY(default)
47 {
48 _GLIBCXX_BEGIN_NAMESPACE_VERSION
49 
50  // [27.6.3] standard manipulators
51  // Also see DR 183.
52 
53  struct _Resetiosflags { ios_base::fmtflags _M_mask; };
54 
55  /**
56  * @brief Manipulator for @c setf.
57  * @param __mask A format flags mask.
58  *
59  * Sent to a stream object, this manipulator resets the specified flags,
60  * via @e stream.setf(0,__mask).
61  */
62  inline _Resetiosflags
63  resetiosflags(ios_base::fmtflags __mask)
64  { return { __mask }; }
65 
66  template<typename _CharT, typename _Traits>
67  inline basic_istream<_CharT, _Traits>&
68  operator>>(basic_istream<_CharT, _Traits>& __is, _Resetiosflags __f)
69  {
70  __is.setf(ios_base::fmtflags(0), __f._M_mask);
71  return __is;
72  }
73 
74  template<typename _CharT, typename _Traits>
75  inline basic_ostream<_CharT, _Traits>&
76  operator<<(basic_ostream<_CharT, _Traits>& __os, _Resetiosflags __f)
77  {
78  __os.setf(ios_base::fmtflags(0), __f._M_mask);
79  return __os;
80  }
81 
82 
83  struct _Setiosflags { ios_base::fmtflags _M_mask; };
84 
85  /**
86  * @brief Manipulator for @c setf.
87  * @param __mask A format flags mask.
88  *
89  * Sent to a stream object, this manipulator sets the format flags
90  * to @a __mask.
91  */
92  inline _Setiosflags
93  setiosflags(ios_base::fmtflags __mask)
94  { return { __mask }; }
95 
96  template<typename _CharT, typename _Traits>
97  inline basic_istream<_CharT, _Traits>&
98  operator>>(basic_istream<_CharT, _Traits>& __is, _Setiosflags __f)
99  {
100  __is.setf(__f._M_mask);
101  return __is;
102  }
103 
104  template<typename _CharT, typename _Traits>
105  inline basic_ostream<_CharT, _Traits>&
106  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setiosflags __f)
107  {
108  __os.setf(__f._M_mask);
109  return __os;
110  }
111 
112 
113  struct _Setbase { int _M_base; };
114 
115  /**
116  * @brief Manipulator for @c setf.
117  * @param __base A numeric base.
118  *
119  * Sent to a stream object, this manipulator changes the
120  * @c ios_base::basefield flags to @c oct, @c dec, or @c hex when @a base
121  * is 8, 10, or 16, accordingly, and to 0 if @a __base is any other value.
122  */
123  inline _Setbase
125  { return { __base }; }
126 
127  template<typename _CharT, typename _Traits>
128  inline basic_istream<_CharT, _Traits>&
129  operator>>(basic_istream<_CharT, _Traits>& __is, _Setbase __f)
130  {
131  __is.setf(__f._M_base == 8 ? ios_base::oct :
132  __f._M_base == 10 ? ios_base::dec :
133  __f._M_base == 16 ? ios_base::hex :
135  return __is;
136  }
137 
138  template<typename _CharT, typename _Traits>
139  inline basic_ostream<_CharT, _Traits>&
140  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setbase __f)
141  {
142  __os.setf(__f._M_base == 8 ? ios_base::oct :
143  __f._M_base == 10 ? ios_base::dec :
144  __f._M_base == 16 ? ios_base::hex :
146  return __os;
147  }
148 
149 
150  template<typename _CharT>
151  struct _Setfill { _CharT _M_c; };
152 
153  /**
154  * @brief Manipulator for @c fill.
155  * @param __c The new fill character.
156  *
157  * Sent to a stream object, this manipulator calls @c fill(__c) for that
158  * object.
159  */
160  template<typename _CharT>
161  inline _Setfill<_CharT>
162  setfill(_CharT __c)
163  { return { __c }; }
164 
165  template<typename _CharT, typename _Traits>
166  inline basic_istream<_CharT, _Traits>&
167  operator>>(basic_istream<_CharT, _Traits>& __is, _Setfill<_CharT> __f)
168  {
169  __is.fill(__f._M_c);
170  return __is;
171  }
172 
173  template<typename _CharT, typename _Traits>
174  inline basic_ostream<_CharT, _Traits>&
175  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setfill<_CharT> __f)
176  {
177  __os.fill(__f._M_c);
178  return __os;
179  }
180 
181 
182  struct _Setprecision { int _M_n; };
183 
184  /**
185  * @brief Manipulator for @c precision.
186  * @param __n The new precision.
187  *
188  * Sent to a stream object, this manipulator calls @c precision(__n) for
189  * that object.
190  */
191  inline _Setprecision
192  setprecision(int __n)
193  { return { __n }; }
194 
195  template<typename _CharT, typename _Traits>
196  inline basic_istream<_CharT, _Traits>&
197  operator>>(basic_istream<_CharT, _Traits>& __is, _Setprecision __f)
198  {
199  __is.precision(__f._M_n);
200  return __is;
201  }
202 
203  template<typename _CharT, typename _Traits>
204  inline basic_ostream<_CharT, _Traits>&
205  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setprecision __f)
206  {
207  __os.precision(__f._M_n);
208  return __os;
209  }
210 
211 
212  struct _Setw { int _M_n; };
213 
214  /**
215  * @brief Manipulator for @c width.
216  * @param __n The new width.
217  *
218  * Sent to a stream object, this manipulator calls @c width(__n) for
219  * that object.
220  */
221  inline _Setw
222  setw(int __n)
223  { return { __n }; }
224 
225  template<typename _CharT, typename _Traits>
226  inline basic_istream<_CharT, _Traits>&
227  operator>>(basic_istream<_CharT, _Traits>& __is, _Setw __f)
228  {
229  __is.width(__f._M_n);
230  return __is;
231  }
232 
233  template<typename _CharT, typename _Traits>
234  inline basic_ostream<_CharT, _Traits>&
235  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setw __f)
236  {
237  __os.width(__f._M_n);
238  return __os;
239  }
240 
241 #if __cplusplus >= 201103L
242 
243  template<typename _MoneyT>
244  struct _Get_money { _MoneyT& _M_mon; bool _M_intl; };
245 
246  /**
247  * @brief Extended manipulator for extracting money.
248  * @param __mon Either long double or a specialization of @c basic_string.
249  * @param __intl A bool indicating whether international format
250  * is to be used.
251  *
252  * Sent to a stream object, this manipulator extracts @a __mon.
253  */
254  template<typename _MoneyT>
255  inline _Get_money<_MoneyT>
256  get_money(_MoneyT& __mon, bool __intl = false)
257  { return { __mon, __intl }; }
258 
259  template<typename _CharT, typename _Traits, typename _MoneyT>
260  basic_istream<_CharT, _Traits>&
261  operator>>(basic_istream<_CharT, _Traits>& __is, _Get_money<_MoneyT> __f)
262  {
263  typename basic_istream<_CharT, _Traits>::sentry __cerb(__is, false);
264  if (__cerb)
265  {
267  __try
268  {
269  typedef istreambuf_iterator<_CharT, _Traits> _Iter;
270  typedef money_get<_CharT, _Iter> _MoneyGet;
271 
272  const _MoneyGet& __mg = use_facet<_MoneyGet>(__is.getloc());
273  __mg.get(_Iter(__is.rdbuf()), _Iter(), __f._M_intl,
274  __is, __err, __f._M_mon);
275  }
277  {
278  __is._M_setstate(ios_base::badbit);
279  __throw_exception_again;
280  }
281  __catch(...)
282  { __is._M_setstate(ios_base::badbit); }
283  if (__err)
284  __is.setstate(__err);
285  }
286  return __is;
287  }
288 
289 
290  template<typename _MoneyT>
291  struct _Put_money { const _MoneyT& _M_mon; bool _M_intl; };
292 
293  /**
294  * @brief Extended manipulator for inserting money.
295  * @param __mon Either long double or a specialization of @c basic_string.
296  * @param __intl A bool indicating whether international format
297  * is to be used.
298  *
299  * Sent to a stream object, this manipulator inserts @a __mon.
300  */
301  template<typename _MoneyT>
302  inline _Put_money<_MoneyT>
303  put_money(const _MoneyT& __mon, bool __intl = false)
304  { return { __mon, __intl }; }
305 
306  template<typename _CharT, typename _Traits, typename _MoneyT>
307  basic_ostream<_CharT, _Traits>&
308  operator<<(basic_ostream<_CharT, _Traits>& __os, _Put_money<_MoneyT> __f)
309  {
310  typename basic_ostream<_CharT, _Traits>::sentry __cerb(__os);
311  if (__cerb)
312  {
314  __try
315  {
316  typedef ostreambuf_iterator<_CharT, _Traits> _Iter;
317  typedef money_put<_CharT, _Iter> _MoneyPut;
318 
319  const _MoneyPut& __mp = use_facet<_MoneyPut>(__os.getloc());
320  if (__mp.put(_Iter(__os.rdbuf()), __f._M_intl, __os,
321  __os.fill(), __f._M_mon).failed())
322  __err |= ios_base::badbit;
323  }
325  {
326  __os._M_setstate(ios_base::badbit);
327  __throw_exception_again;
328  }
329  __catch(...)
330  { __os._M_setstate(ios_base::badbit); }
331  if (__err)
332  __os.setstate(__err);
333  }
334  return __os;
335  }
336 
337 #if __cplusplus > 201103L
338 
339 _GLIBCXX_END_NAMESPACE_VERSION
340  namespace __detail {
341  _GLIBCXX_BEGIN_NAMESPACE_VERSION
342 
343  /**
344  * @brief Struct for delimited strings.
345  * The left and right delimiters can be different.
346  */
347  template<typename _String, typename _CharT>
348  struct _Quoted_string
349  {
350  static_assert(is_reference<_String>::value
351  || is_pointer<_String>::value,
352  "String type must be pointer or reference");
353 
354  _Quoted_string(_String __str, _CharT __del, _CharT __esc)
355  : _M_string(__str), _M_delim{__del}, _M_escape{__esc}
356  { }
357 
358  _Quoted_string&
359  operator=(_Quoted_string&) = delete;
360 
361  _String _M_string;
362  _CharT _M_delim;
363  _CharT _M_escape;
364  };
365 
366  /**
367  * @brief Inserter for delimited strings.
368  * The left and right delimiters can be different.
369  */
370  template<typename _CharT, typename _Traits>
371  auto&
372  operator<<(std::basic_ostream<_CharT, _Traits>& __os,
373  const _Quoted_string<const _CharT*, _CharT>& __str)
374  {
375  __os << __str._M_delim;
376  for (const _CharT* __c = __str._M_string; *__c; ++__c)
377  {
378  if (*__c == __str._M_delim || *__c == __str._M_escape)
379  __os << __str._M_escape;
380  __os << *__c;
381  }
382  __os << __str._M_delim;
383 
384  return __os;
385  }
386 
387  /**
388  * @brief Inserter for delimited strings.
389  * The left and right delimiters can be different.
390  */
391  template<typename _CharT, typename _Traits, typename _String>
392  auto&
393  operator<<(std::basic_ostream<_CharT, _Traits>& __os,
394  const _Quoted_string<_String, _CharT>& __str)
395  {
396  __os << __str._M_delim;
397  for (auto& __c : __str._M_string)
398  {
399  if (__c == __str._M_delim || __c == __str._M_escape)
400  __os << __str._M_escape;
401  __os << __c;
402  }
403  __os << __str._M_delim;
404 
405  return __os;
406  }
407 
408  /**
409  * @brief Extractor for delimited strings.
410  * The left and right delimiters can be different.
411  */
412  template<typename _CharT, typename _Traits, typename _Alloc>
413  auto&
415  const _Quoted_string<basic_string<_CharT, _Traits, _Alloc>&,
416  _CharT>& __str)
417  {
418  __str._M_string.clear();
419 
420  _CharT __c;
421  __is >> __c;
422  if (!__is.good())
423  return __is;
424  if (__c != __str._M_delim)
425  {
426  __is.unget();
427  __is >> __str._M_string;
428  return __is;
429  }
430  std::ios_base::fmtflags __flags
431  = __is.flags(__is.flags() & ~std::ios_base::skipws);
432  do
433  {
434  __is >> __c;
435  if (!__is.good())
436  break;
437  if (__c == __str._M_escape)
438  {
439  __is >> __c;
440  if (!__is.good())
441  break;
442  }
443  else if (__c == __str._M_delim)
444  break;
445  __str._M_string += __c;
446  }
447  while (true);
448  __is.setf(__flags);
449 
450  return __is;
451  }
452  _GLIBCXX_END_NAMESPACE_VERSION
453  } // namespace __detail
454 _GLIBCXX_BEGIN_NAMESPACE_VERSION
455 
456  /**
457  * @brief Manipulator for quoted strings.
458  * @param __str String to quote.
459  * @param __delim Character to quote string with.
460  * @param __escape Escape character to escape itself or quote character.
461  */
462  template<typename _CharT>
463  inline auto
464  quoted(const _CharT* __string,
465  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
466  {
467  return __detail::_Quoted_string<const _CharT*, _CharT>(__string, __delim,
468  __escape);
469  }
470 
471  template<typename _CharT, typename _Traits, typename _Alloc>
472  inline auto
473  quoted(const basic_string<_CharT, _Traits, _Alloc>& __string,
474  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
475  {
476  return __detail::_Quoted_string<
477  const basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
478  __string, __delim, __escape);
479  }
480 
481  template<typename _CharT, typename _Traits, typename _Alloc>
482  inline auto
483  quoted(basic_string<_CharT, _Traits, _Alloc>& __string,
484  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
485  {
486  return __detail::_Quoted_string<
487  basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
488  __string, __delim, __escape);
489  }
490 
491 #endif // __cplusplus > 201103L
492 
493 #endif // __cplusplus >= 201103L
494 
495  // Inhibit implicit instantiations for required instantiations,
496  // which are defined via explicit instantiations elsewhere.
497  // NB: This syntax is a GNU extension.
498 #if _GLIBCXX_EXTERN_TEMPLATE
499  extern template ostream& operator<<(ostream&, _Setfill<char>);
500  extern template ostream& operator<<(ostream&, _Setiosflags);
501  extern template ostream& operator<<(ostream&, _Resetiosflags);
502  extern template ostream& operator<<(ostream&, _Setbase);
503  extern template ostream& operator<<(ostream&, _Setprecision);
504  extern template ostream& operator<<(ostream&, _Setw);
505  extern template istream& operator>>(istream&, _Setfill<char>);
506  extern template istream& operator>>(istream&, _Setiosflags);
507  extern template istream& operator>>(istream&, _Resetiosflags);
508  extern template istream& operator>>(istream&, _Setbase);
509  extern template istream& operator>>(istream&, _Setprecision);
510  extern template istream& operator>>(istream&, _Setw);
511 
512 #ifdef _GLIBCXX_USE_WCHAR_T
513  extern template wostream& operator<<(wostream&, _Setfill<wchar_t>);
514  extern template wostream& operator<<(wostream&, _Setiosflags);
515  extern template wostream& operator<<(wostream&, _Resetiosflags);
516  extern template wostream& operator<<(wostream&, _Setbase);
517  extern template wostream& operator<<(wostream&, _Setprecision);
518  extern template wostream& operator<<(wostream&, _Setw);
519  extern template wistream& operator>>(wistream&, _Setfill<wchar_t>);
520  extern template wistream& operator>>(wistream&, _Setiosflags);
521  extern template wistream& operator>>(wistream&, _Resetiosflags);
522  extern template wistream& operator>>(wistream&, _Setbase);
523  extern template wistream& operator>>(wistream&, _Setprecision);
524  extern template wistream& operator>>(wistream&, _Setw);
525 #endif
526 #endif
527 
528 _GLIBCXX_END_NAMESPACE_VERSION
529 } // namespace
530 
531 #endif /* _GLIBCXX_IOMANIP */
__istream_type & unget()
Unextracting the previous character.
Definition: istream.tcc:746
bool good() const
Fast error checking.
Definition: basic_ios.h:174
static const fmtflags basefield
A mask of dec|oct|hex. Useful for the 2-arg form of setf.
Definition: ios_base.h:313
_Ios_Iostate iostate
This is a bitmask type.
Definition: ios_base.h:330
_Setbase setbase(int __base)
Manipulator for setf.
Definition: iomanip:124
_Ios_Fmtflags fmtflags
This is a bitmask type.
Definition: ios_base.h:255
fmtflags setf(fmtflags __fmtfl)
Setting new format flags.
Definition: ios_base.h:578
basic_istream< wchar_t > wistream
Base class for wchar_t input streams.
Definition: iosfwd:173
Template class basic_istream.
Definition: iosfwd:83
basic_ostream< wchar_t > wostream
Base class for wchar_t output streams.
Definition: iosfwd:176
static const iostate goodbit
Indicates all is well.
Definition: ios_base.h:345
_Put_money< _MoneyT > put_money(const _MoneyT &__mon, bool __intl=false)
Extended manipulator for inserting money.
Definition: iomanip:303
static const iostate badbit
Indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error fro...
Definition: ios_base.h:334
static const fmtflags oct
Converts integer input or generates integer output in octal base.
Definition: ios_base.h:279
static const fmtflags dec
Converts integer input or generates integer output in decimal base.
Definition: ios_base.h:261
bitset< _Nb > operator<<(size_t __position) const noexcept
Self-explanatory.
Definition: bitset:1349
_Setfill< _CharT > setfill(_CharT __c)
Manipulator for fill.
Definition: iomanip:162
basic_istream< char > istream
Base class for char input streams.
Definition: iosfwd:133
_Setprecision setprecision(int __n)
Manipulator for precision.
Definition: iomanip:192
Thrown as part of forced unwinding.A magic placeholder class that can be caught by reference to recog...
Definition: cxxabi_forced.h:48
_Resetiosflags resetiosflags(ios_base::fmtflags __mask)
Manipulator for setf.
Definition: iomanip:63
_Get_money< _MoneyT > get_money(_MoneyT &__mon, bool __intl=false)
Extended manipulator for extracting money.
Definition: iomanip:256
ios_base & skipws(ios_base &__base)
Calls base.setf(ios_base::skipws).
Definition: ios_base.h:859
_Setw setw(int __n)
Manipulator for width.
Definition: iomanip:222
basic_ostream< char > ostream
Base class for char output streams.
Definition: iosfwd:136
bitset< _Nb > operator>>(size_t __position) const noexcept
Self-explanatory.
Definition: bitset:1353
static const fmtflags hex
Converts integer input or generates integer output in hexadecimal base.
Definition: ios_base.h:267
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:551
_Siter_base< _Iterator >::iterator_type __base(_Iterator __it)
Definition: functions.h:558
_Setiosflags setiosflags(ios_base::fmtflags __mask)
Manipulator for setf.
Definition: iomanip:93