libstdc++
iomanip
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1 // Standard stream manipulators -*- C++ -*-
2 
3 // Copyright (C) 1997-2013 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  namespace __detail {
340 
341  /**
342  * @brief Struct for delimited strings.
343  * The left and right delimiters can be different.
344  */
345  template<typename _String, typename _CharT>
346  struct _Quoted_string
347  {
348  static_assert(is_reference<_String>::value
349  || is_pointer<_String>::value,
350  "String type must be pointer or reference");
351 
352  _Quoted_string(_String __str, _CharT __del, _CharT __esc)
353  : _M_string(__str), _M_delim{__del}, _M_escape{__esc}
354  { }
355 
356  _Quoted_string&
357  operator=(_Quoted_string&) = delete;
358 
359  _String _M_string;
360  _CharT _M_delim;
361  _CharT _M_escape;
362  };
363 
364  /**
365  * @brief Inserter for delimited strings.
366  * The left and right delimiters can be different.
367  */
368  template<typename _CharT, typename _Traits>
369  auto&
370  operator<<(std::basic_ostream<_CharT, _Traits>& __os,
371  const _Quoted_string<const _CharT*, _CharT>& __str)
372  {
373  __os << __str._M_delim;
374  for (const _CharT* __c = __str._M_string; *__c; ++__c)
375  {
376  if (*__c == __str._M_delim || *__c == __str._M_escape)
377  __os << __str._M_escape;
378  __os << *__c;
379  }
380  __os << __str._M_delim;
381 
382  return __os;
383  }
384 
385  /**
386  * @brief Inserter for delimited strings.
387  * The left and right delimiters can be different.
388  */
389  template<typename _CharT, typename _Traits, typename _String>
390  auto&
391  operator<<(std::basic_ostream<_CharT, _Traits>& __os,
392  const _Quoted_string<_String, _CharT>& __str)
393  {
394  __os << __str._M_delim;
395  for (auto& __c : __str._M_string)
396  {
397  if (__c == __str._M_delim || __c == __str._M_escape)
398  __os << __str._M_escape;
399  __os << __c;
400  }
401  __os << __str._M_delim;
402 
403  return __os;
404  }
405 
406  /**
407  * @brief Extractor for delimited strings.
408  * The left and right delimiters can be different.
409  */
410  template<typename _CharT, typename _Traits, typename _Alloc>
411  auto&
413  const _Quoted_string<basic_string<_CharT, _Traits, _Alloc>&,
414  _CharT>& __str)
415  {
416  __str._M_string.clear();
417 
418  _CharT __c;
419  __is >> __c;
420  if (!__is.good())
421  return __is;
422  if (__c != __str._M_delim)
423  {
424  __is.unget();
425  __is >> __str._M_string;
426  return __is;
427  }
428  std::ios_base::fmtflags __flags
429  = __is.flags(__is.flags() & ~std::ios_base::skipws);
430  do
431  {
432  __is >> __c;
433  if (!__is.good())
434  break;
435  if (__c == __str._M_escape)
436  {
437  __is >> __c;
438  if (!__is.good())
439  break;
440  }
441  else if (__c == __str._M_delim)
442  break;
443  __str._M_string += __c;
444  }
445  while (true);
446  __is.setf(__flags);
447 
448  return __is;
449  }
450 
451  } // namespace __detail
452 
453  /**
454  * @brief Manipulator for quoted strings.
455  * @param __str 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 #endif // __cplusplus > 201103L
489 
490 #endif // __cplusplus >= 201103L
491 
492  // Inhibit implicit instantiations for required instantiations,
493  // which are defined via explicit instantiations elsewhere.
494  // NB: This syntax is a GNU extension.
495 #if _GLIBCXX_EXTERN_TEMPLATE
496  extern template ostream& operator<<(ostream&, _Setfill<char>);
497  extern template ostream& operator<<(ostream&, _Setiosflags);
498  extern template ostream& operator<<(ostream&, _Resetiosflags);
499  extern template ostream& operator<<(ostream&, _Setbase);
500  extern template ostream& operator<<(ostream&, _Setprecision);
501  extern template ostream& operator<<(ostream&, _Setw);
502  extern template istream& operator>>(istream&, _Setfill<char>);
503  extern template istream& operator>>(istream&, _Setiosflags);
504  extern template istream& operator>>(istream&, _Resetiosflags);
505  extern template istream& operator>>(istream&, _Setbase);
506  extern template istream& operator>>(istream&, _Setprecision);
507  extern template istream& operator>>(istream&, _Setw);
508 
509 #ifdef _GLIBCXX_USE_WCHAR_T
510  extern template wostream& operator<<(wostream&, _Setfill<wchar_t>);
511  extern template wostream& operator<<(wostream&, _Setiosflags);
512  extern template wostream& operator<<(wostream&, _Resetiosflags);
513  extern template wostream& operator<<(wostream&, _Setbase);
514  extern template wostream& operator<<(wostream&, _Setprecision);
515  extern template wostream& operator<<(wostream&, _Setw);
516  extern template wistream& operator>>(wistream&, _Setfill<wchar_t>);
517  extern template wistream& operator>>(wistream&, _Setiosflags);
518  extern template wistream& operator>>(wistream&, _Resetiosflags);
519  extern template wistream& operator>>(wistream&, _Setbase);
520  extern template wistream& operator>>(wistream&, _Setprecision);
521  extern template wistream& operator>>(wistream&, _Setw);
522 #endif
523 #endif
524 
525 _GLIBCXX_END_NAMESPACE_VERSION
526 } // namespace
527 
528 #endif /* _GLIBCXX_IOMANIP */