libstdc++
iomanip
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1 // Standard stream manipulators -*- C++ -*-
2 
3 // Copyright (C) 1997-2020 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 #if __cplusplus > 201103L
45 #include <bits/quoted_string.h>
46 #endif
47 #endif
48 
49 namespace std _GLIBCXX_VISIBILITY(default)
50 {
51 _GLIBCXX_BEGIN_NAMESPACE_VERSION
52 
53  // [27.6.3] standard manipulators
54  // Also see DR 183.
55 
56  struct _Resetiosflags { ios_base::fmtflags _M_mask; };
57 
58  /**
59  * @brief Manipulator for @c setf.
60  * @param __mask A format flags mask.
61  *
62  * Sent to a stream object, this manipulator resets the specified flags,
63  * via @e stream.setf(0,__mask).
64  */
65  inline _Resetiosflags
66  resetiosflags(ios_base::fmtflags __mask)
67  { return { __mask }; }
68 
69  template<typename _CharT, typename _Traits>
70  inline basic_istream<_CharT, _Traits>&
71  operator>>(basic_istream<_CharT, _Traits>& __is, _Resetiosflags __f)
72  {
73  __is.setf(ios_base::fmtflags(0), __f._M_mask);
74  return __is;
75  }
76 
77  template<typename _CharT, typename _Traits>
78  inline basic_ostream<_CharT, _Traits>&
79  operator<<(basic_ostream<_CharT, _Traits>& __os, _Resetiosflags __f)
80  {
81  __os.setf(ios_base::fmtflags(0), __f._M_mask);
82  return __os;
83  }
84 
85 
86  struct _Setiosflags { ios_base::fmtflags _M_mask; };
87 
88  /**
89  * @brief Manipulator for @c setf.
90  * @param __mask A format flags mask.
91  *
92  * Sent to a stream object, this manipulator sets the format flags
93  * to @a __mask.
94  */
95  inline _Setiosflags
96  setiosflags(ios_base::fmtflags __mask)
97  { return { __mask }; }
98 
99  template<typename _CharT, typename _Traits>
100  inline basic_istream<_CharT, _Traits>&
101  operator>>(basic_istream<_CharT, _Traits>& __is, _Setiosflags __f)
102  {
103  __is.setf(__f._M_mask);
104  return __is;
105  }
106 
107  template<typename _CharT, typename _Traits>
108  inline basic_ostream<_CharT, _Traits>&
109  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setiosflags __f)
110  {
111  __os.setf(__f._M_mask);
112  return __os;
113  }
114 
115 
116  struct _Setbase { int _M_base; };
117 
118  /**
119  * @brief Manipulator for @c setf.
120  * @param __base A numeric base.
121  *
122  * Sent to a stream object, this manipulator changes the
123  * @c ios_base::basefield flags to @c oct, @c dec, or @c hex when @a base
124  * is 8, 10, or 16, accordingly, and to 0 if @a __base is any other value.
125  */
126  inline _Setbase
127  setbase(int __base)
128  { return { __base }; }
129 
130  template<typename _CharT, typename _Traits>
131  inline basic_istream<_CharT, _Traits>&
132  operator>>(basic_istream<_CharT, _Traits>& __is, _Setbase __f)
133  {
134  __is.setf(__f._M_base == 8 ? ios_base::oct :
135  __f._M_base == 10 ? ios_base::dec :
136  __f._M_base == 16 ? ios_base::hex :
137  ios_base::fmtflags(0), ios_base::basefield);
138  return __is;
139  }
140 
141  template<typename _CharT, typename _Traits>
142  inline basic_ostream<_CharT, _Traits>&
143  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setbase __f)
144  {
145  __os.setf(__f._M_base == 8 ? ios_base::oct :
146  __f._M_base == 10 ? ios_base::dec :
147  __f._M_base == 16 ? ios_base::hex :
148  ios_base::fmtflags(0), ios_base::basefield);
149  return __os;
150  }
151 
152 
153  template<typename _CharT>
154  struct _Setfill { _CharT _M_c; };
155 
156  /**
157  * @brief Manipulator for @c fill.
158  * @param __c The new fill character.
159  *
160  * Sent to a stream object, this manipulator calls @c fill(__c) for that
161  * object.
162  */
163  template<typename _CharT>
164  inline _Setfill<_CharT>
165  setfill(_CharT __c)
166  { return { __c }; }
167 
168  template<typename _CharT, typename _Traits>
169  inline basic_istream<_CharT, _Traits>&
170  operator>>(basic_istream<_CharT, _Traits>& __is, _Setfill<_CharT> __f)
171  {
172  __is.fill(__f._M_c);
173  return __is;
174  }
175 
176  template<typename _CharT, typename _Traits>
177  inline basic_ostream<_CharT, _Traits>&
178  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setfill<_CharT> __f)
179  {
180  __os.fill(__f._M_c);
181  return __os;
182  }
183 
184 
185  struct _Setprecision { int _M_n; };
186 
187  /**
188  * @brief Manipulator for @c precision.
189  * @param __n The new precision.
190  *
191  * Sent to a stream object, this manipulator calls @c precision(__n) for
192  * that object.
193  */
194  inline _Setprecision
195  setprecision(int __n)
196  { return { __n }; }
197 
198  template<typename _CharT, typename _Traits>
199  inline basic_istream<_CharT, _Traits>&
200  operator>>(basic_istream<_CharT, _Traits>& __is, _Setprecision __f)
201  {
202  __is.precision(__f._M_n);
203  return __is;
204  }
205 
206  template<typename _CharT, typename _Traits>
207  inline basic_ostream<_CharT, _Traits>&
208  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setprecision __f)
209  {
210  __os.precision(__f._M_n);
211  return __os;
212  }
213 
214 
215  struct _Setw { int _M_n; };
216 
217  /**
218  * @brief Manipulator for @c width.
219  * @param __n The new width.
220  *
221  * Sent to a stream object, this manipulator calls @c width(__n) for
222  * that object.
223  */
224  inline _Setw
225  setw(int __n)
226  { return { __n }; }
227 
228  template<typename _CharT, typename _Traits>
229  inline basic_istream<_CharT, _Traits>&
230  operator>>(basic_istream<_CharT, _Traits>& __is, _Setw __f)
231  {
232  __is.width(__f._M_n);
233  return __is;
234  }
235 
236  template<typename _CharT, typename _Traits>
237  inline basic_ostream<_CharT, _Traits>&
238  operator<<(basic_ostream<_CharT, _Traits>& __os, _Setw __f)
239  {
240  __os.width(__f._M_n);
241  return __os;
242  }
243 
244 #if __cplusplus >= 201103L
245 
246  template<typename _MoneyT>
247  struct _Get_money { _MoneyT& _M_mon; bool _M_intl; };
248 
249  /**
250  * @brief Extended manipulator for extracting money.
251  * @param __mon Either long double or a specialization of @c basic_string.
252  * @param __intl A bool indicating whether international format
253  * is to be used.
254  *
255  * Sent to a stream object, this manipulator extracts @a __mon.
256  */
257  template<typename _MoneyT>
258  inline _Get_money<_MoneyT>
259  get_money(_MoneyT& __mon, bool __intl = false)
260  { return { __mon, __intl }; }
261 
262  template<typename _CharT, typename _Traits, typename _MoneyT>
263  basic_istream<_CharT, _Traits>&
264  operator>>(basic_istream<_CharT, _Traits>& __is, _Get_money<_MoneyT> __f)
265  {
266  typename basic_istream<_CharT, _Traits>::sentry __cerb(__is, false);
267  if (__cerb)
268  {
269  ios_base::iostate __err = ios_base::goodbit;
270  __try
271  {
272  typedef istreambuf_iterator<_CharT, _Traits> _Iter;
273  typedef money_get<_CharT, _Iter> _MoneyGet;
274 
275  const _MoneyGet& __mg = use_facet<_MoneyGet>(__is.getloc());
276  __mg.get(_Iter(__is.rdbuf()), _Iter(), __f._M_intl,
277  __is, __err, __f._M_mon);
278  }
279  __catch(__cxxabiv1::__forced_unwind&)
280  {
281  __is._M_setstate(ios_base::badbit);
282  __throw_exception_again;
283  }
284  __catch(...)
285  { __is._M_setstate(ios_base::badbit); }
286  if (__err)
287  __is.setstate(__err);
288  }
289  return __is;
290  }
291 
292 
293  template<typename _MoneyT>
294  struct _Put_money { const _MoneyT& _M_mon; bool _M_intl; };
295 
296  /**
297  * @brief Extended manipulator for inserting money.
298  * @param __mon Either long double or a specialization of @c basic_string.
299  * @param __intl A bool indicating whether international format
300  * is to be used.
301  *
302  * Sent to a stream object, this manipulator inserts @a __mon.
303  */
304  template<typename _MoneyT>
305  inline _Put_money<_MoneyT>
306  put_money(const _MoneyT& __mon, bool __intl = false)
307  { return { __mon, __intl }; }
308 
309  template<typename _CharT, typename _Traits, typename _MoneyT>
310  basic_ostream<_CharT, _Traits>&
311  operator<<(basic_ostream<_CharT, _Traits>& __os, _Put_money<_MoneyT> __f)
312  {
313  typename basic_ostream<_CharT, _Traits>::sentry __cerb(__os);
314  if (__cerb)
315  {
316  ios_base::iostate __err = ios_base::goodbit;
317  __try
318  {
319  typedef ostreambuf_iterator<_CharT, _Traits> _Iter;
320  typedef money_put<_CharT, _Iter> _MoneyPut;
321 
322  const _MoneyPut& __mp = use_facet<_MoneyPut>(__os.getloc());
323  if (__mp.put(_Iter(__os.rdbuf()), __f._M_intl, __os,
324  __os.fill(), __f._M_mon).failed())
325  __err |= ios_base::badbit;
326  }
327  __catch(__cxxabiv1::__forced_unwind&)
328  {
329  __os._M_setstate(ios_base::badbit);
330  __throw_exception_again;
331  }
332  __catch(...)
333  { __os._M_setstate(ios_base::badbit); }
334  if (__err)
335  __os.setstate(__err);
336  }
337  return __os;
338  }
339 
340  template<typename _CharT>
341  struct _Put_time
342  {
343  const std::tm* _M_tmb;
344  const _CharT* _M_fmt;
345  };
346 
347  /**
348  * @brief Extended manipulator for formatting time.
349  *
350  * This manipulator uses time_put::put to format time.
351  * [ext.manip]
352  *
353  * @param __tmb struct tm time data to format.
354  * @param __fmt format string.
355  */
356  template<typename _CharT>
357  inline _Put_time<_CharT>
358  put_time(const std::tm* __tmb, const _CharT* __fmt)
359  { return { __tmb, __fmt }; }
360 
361  template<typename _CharT, typename _Traits>
362  basic_ostream<_CharT, _Traits>&
363  operator<<(basic_ostream<_CharT, _Traits>& __os, _Put_time<_CharT> __f)
364  {
365  typename basic_ostream<_CharT, _Traits>::sentry __cerb(__os);
366  if (__cerb)
367  {
368  ios_base::iostate __err = ios_base::goodbit;
369  __try
370  {
371  typedef ostreambuf_iterator<_CharT, _Traits> _Iter;
372  typedef time_put<_CharT, _Iter> _TimePut;
373 
374  const _CharT* const __fmt_end = __f._M_fmt +
375  _Traits::length(__f._M_fmt);
376 
377  const _TimePut& __mp = use_facet<_TimePut>(__os.getloc());
378  if (__mp.put(_Iter(__os.rdbuf()), __os, __os.fill(),
379  __f._M_tmb, __f._M_fmt, __fmt_end).failed())
380  __err |= ios_base::badbit;
381  }
382  __catch(__cxxabiv1::__forced_unwind&)
383  {
384  __os._M_setstate(ios_base::badbit);
385  __throw_exception_again;
386  }
387  __catch(...)
388  { __os._M_setstate(ios_base::badbit); }
389  if (__err)
390  __os.setstate(__err);
391  }
392  return __os;
393  }
394 
395  template<typename _CharT>
396  struct _Get_time
397  {
398  std::tm* _M_tmb;
399  const _CharT* _M_fmt;
400  };
401 
402  /**
403  * @brief Extended manipulator for extracting time.
404  *
405  * This manipulator uses time_get::get to extract time.
406  * [ext.manip]
407  *
408  * @param __tmb struct to extract the time data to.
409  * @param __fmt format string.
410  */
411  template<typename _CharT>
412  inline _Get_time<_CharT>
413  get_time(std::tm* __tmb, const _CharT* __fmt)
414  { return { __tmb, __fmt }; }
415 
416  template<typename _CharT, typename _Traits>
417  basic_istream<_CharT, _Traits>&
418  operator>>(basic_istream<_CharT, _Traits>& __is, _Get_time<_CharT> __f)
419  {
420  typename basic_istream<_CharT, _Traits>::sentry __cerb(__is, false);
421  if (__cerb)
422  {
423  ios_base::iostate __err = ios_base::goodbit;
424  __try
425  {
426  typedef istreambuf_iterator<_CharT, _Traits> _Iter;
427  typedef time_get<_CharT, _Iter> _TimeGet;
428 
429  const _CharT* const __fmt_end = __f._M_fmt +
430  _Traits::length(__f._M_fmt);
431 
432  const _TimeGet& __mg = use_facet<_TimeGet>(__is.getloc());
433  __mg.get(_Iter(__is.rdbuf()), _Iter(), __is,
434  __err, __f._M_tmb, __f._M_fmt, __fmt_end);
435  }
436  __catch(__cxxabiv1::__forced_unwind&)
437  {
438  __is._M_setstate(ios_base::badbit);
439  __throw_exception_again;
440  }
441  __catch(...)
442  { __is._M_setstate(ios_base::badbit); }
443  if (__err)
444  __is.setstate(__err);
445  }
446  return __is;
447  }
448 
449 #if __cplusplus >= 201402L
450 
451 #define __cpp_lib_quoted_string_io 201304
452 
453  /**
454  * @brief Manipulator for quoted strings.
455  * @param __string String to quote.
456  * @param __delim Character to quote string with.
457  * @param __escape Escape character to escape itself or quote character.
458  */
459  template<typename _CharT>
460  inline auto
461  quoted(const _CharT* __string,
462  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
463  {
464  return __detail::_Quoted_string<const _CharT*, _CharT>(__string, __delim,
465  __escape);
466  }
467 
468  template<typename _CharT, typename _Traits, typename _Alloc>
469  inline auto
470  quoted(const basic_string<_CharT, _Traits, _Alloc>& __string,
471  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
472  {
473  return __detail::_Quoted_string<
474  const basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
475  __string, __delim, __escape);
476  }
477 
478  template<typename _CharT, typename _Traits, typename _Alloc>
479  inline auto
480  quoted(basic_string<_CharT, _Traits, _Alloc>& __string,
481  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
482  {
483  return __detail::_Quoted_string<
484  basic_string<_CharT, _Traits, _Alloc>&, _CharT>(
485  __string, __delim, __escape);
486  }
487 
488 #if __cplusplus >= 201703L
489  // _GLIBCXX_RESOLVE_LIB_DEFECTS
490  // 2785. quoted should work with basic_string_view
491  template<typename _CharT, typename _Traits>
492  inline auto
493  quoted(basic_string_view<_CharT, _Traits> __sv,
494  _CharT __delim = _CharT('"'), _CharT __escape = _CharT('\\'))
495  {
496  return __detail::_Quoted_string<
497  basic_string_view<_CharT, _Traits>, _CharT>(__sv, __delim, __escape);
498  }
499 #endif // C++17
500 #endif // C++14
501 
502 #endif // __cplusplus >= 201103L
503 
504  // Inhibit implicit instantiations for required instantiations,
505  // which are defined via explicit instantiations elsewhere.
506  // NB: This syntax is a GNU extension.
507 #if _GLIBCXX_EXTERN_TEMPLATE
508  extern template ostream& operator<<(ostream&, _Setfill<char>);
509  extern template ostream& operator<<(ostream&, _Setiosflags);
510  extern template ostream& operator<<(ostream&, _Resetiosflags);
511  extern template ostream& operator<<(ostream&, _Setbase);
512  extern template ostream& operator<<(ostream&, _Setprecision);
513  extern template ostream& operator<<(ostream&, _Setw);
514  extern template istream& operator>>(istream&, _Setfill<char>);
515  extern template istream& operator>>(istream&, _Setiosflags);
516  extern template istream& operator>>(istream&, _Resetiosflags);
517  extern template istream& operator>>(istream&, _Setbase);
518  extern template istream& operator>>(istream&, _Setprecision);
519  extern template istream& operator>>(istream&, _Setw);
520 
521 #ifdef _GLIBCXX_USE_WCHAR_T
522  extern template wostream& operator<<(wostream&, _Setfill<wchar_t>);
523  extern template wostream& operator<<(wostream&, _Setiosflags);
524  extern template wostream& operator<<(wostream&, _Resetiosflags);
525  extern template wostream& operator<<(wostream&, _Setbase);
526  extern template wostream& operator<<(wostream&, _Setprecision);
527  extern template wostream& operator<<(wostream&, _Setw);
528  extern template wistream& operator>>(wistream&, _Setfill<wchar_t>);
529  extern template wistream& operator>>(wistream&, _Setiosflags);
530  extern template wistream& operator>>(wistream&, _Resetiosflags);
531  extern template wistream& operator>>(wistream&, _Setbase);
532  extern template wistream& operator>>(wistream&, _Setprecision);
533  extern template wistream& operator>>(wistream&, _Setw);
534 #endif
535 #endif
536 
537 _GLIBCXX_END_NAMESPACE_VERSION
538 } // namespace
539 
540 #endif /* _GLIBCXX_IOMANIP */