summaryrefslogtreecommitdiffstats
blob: 0ca9baa7aed0d3f2ca9ead08ef07e4e0892dd727 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
/*
 *
 * Copyright (c) 1998-2009 John Maddock
 * Copyright 2008 Eric Niebler. 
 *
 * Use, modification and distribution are subject to the 
 * Boost Software License, Version 1.0. (See accompanying file 
 * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 *
 */

 /*
  *   LOCATION:    see http://www.boost.org for most recent version.
  *   FILE         regex_format.hpp
  *   VERSION      see <boost/version.hpp>
  *   DESCRIPTION: Provides formatting output routines for search and replace
  *                operations.  Note this is an internal header file included
  *                by regex.hpp, do not include on its own.
  */

#ifndef BOOST_REGEX_FORMAT_HPP
#define BOOST_REGEX_FORMAT_HPP

#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/is_function.hpp>
#include <boost/type_traits/is_class.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/is_convertible.hpp>
#include <boost/type_traits/remove_pointer.hpp>
#include <boost/type_traits/remove_cv.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/and.hpp>
#include <boost/mpl/not.hpp>
#ifndef BOOST_NO_SFINAE
#include <boost/mpl/has_xxx.hpp>
#endif

namespace boost{

#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable: 4103)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
#  include BOOST_ABI_PREFIX
#endif
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif

//
// Forward declaration:
//
   template <class BidiIterator, class Allocator = BOOST_DEDUCED_TYPENAME std::vector<sub_match<BidiIterator> >::allocator_type >
class match_results;

namespace re_detail{

//
// struct trivial_format_traits:
// defines minimum localisation support for formatting
// in the case that the actual regex traits is unavailable.
//
template <class charT>
struct trivial_format_traits
{
   typedef charT char_type;

   static std::ptrdiff_t length(const charT* p)
   {
      return global_length(p);
   }
   static charT tolower(charT c)
   {
      return ::boost::re_detail::global_lower(c);
   }
   static charT toupper(charT c)
   {
      return ::boost::re_detail::global_upper(c);
   }
   static int value(const charT c, int radix)
   {
      int result = global_value(c);
      return result >= radix ? -1 : result;
   }
   int toi(const charT*& p1, const charT* p2, int radix)const
   {
      return global_toi(p1, p2, radix, *this);
   }
};

template <class OutputIterator, class Results, class traits, class ForwardIter>
class basic_regex_formatter
{
public:
   typedef typename traits::char_type char_type;
   basic_regex_formatter(OutputIterator o, const Results& r, const traits& t)
      : m_traits(t), m_results(r), m_out(o), m_state(output_copy), m_restore_state(output_copy), m_have_conditional(false) {}
   OutputIterator format(ForwardIter p1, ForwardIter p2, match_flag_type f);
   OutputIterator format(ForwardIter p1, match_flag_type f)
   {
      return format(p1, p1 + m_traits.length(p1), f);
   }
private:
   typedef typename Results::value_type sub_match_type;
   enum output_state
   {
      output_copy,
      output_next_lower,
      output_next_upper,
      output_lower,
      output_upper,
      output_none
   };

   void put(char_type c);
   void put(const sub_match_type& sub);
   void format_all();
   void format_perl();
   void format_escape();
   void format_conditional();
   void format_until_scope_end();
   bool handle_perl_verb(bool have_brace);

   inline typename Results::value_type const& get_named_sub(ForwardIter i, ForwardIter j, const mpl::false_&)
   {
      std::vector<char_type> v(i, j);
      return (i != j) ? this->m_results.named_subexpression(&v[0], &v[0] + v.size())
         : this->m_results.named_subexpression(static_cast<const char_type*>(0), static_cast<const char_type*>(0));
   }
   inline typename Results::value_type const& get_named_sub(ForwardIter i, ForwardIter j, const mpl::true_&)
   {
      return this->m_results.named_subexpression(i, j);
   }
   inline typename Results::value_type const& get_named_sub(ForwardIter i, ForwardIter j)
   {
      typedef typename boost::is_convertible<ForwardIter, const char_type*>::type tag_type;
      return get_named_sub(i, j, tag_type());
   }
   inline int get_named_sub_index(ForwardIter i, ForwardIter j, const mpl::false_&)
   {
      std::vector<char_type> v(i, j);
      return (i != j) ? this->m_results.named_subexpression_index(&v[0], &v[0] + v.size())
         : this->m_results.named_subexpression_index(static_cast<const char_type*>(0), static_cast<const char_type*>(0));
   }
   inline int get_named_sub_index(ForwardIter i, ForwardIter j, const mpl::true_&)
   {
      return this->m_results.named_subexpression_index(i, j);
   }
   inline int get_named_sub_index(ForwardIter i, ForwardIter j)
   {
      typedef typename boost::is_convertible<ForwardIter, const char_type*>::type tag_type;
      return get_named_sub_index(i, j, tag_type());
   }
   inline int toi(ForwardIter& i, ForwardIter j, int base, const boost::mpl::false_&)
   {
      if(i != j)
      {
         std::vector<char_type> v(i, j);
         const char_type* start = &v[0];
         const char_type* pos = start;
         int r = m_traits.toi(pos, &v[0] + v.size(), base);
         std::advance(i, pos - start);
         return r;
      }
      return -1;
   }
   inline int toi(ForwardIter& i, ForwardIter j, int base, const boost::mpl::true_&)
   {
      return m_traits.toi(i, j, base);
   }
   inline int toi(ForwardIter& i, ForwardIter j, int base)
   {
      typedef typename boost::is_convertible<ForwardIter, const char_type*&>::type tag_type;
      return toi(i, j, base, tag_type());
   }

   const traits&    m_traits;       // the traits class for localised formatting operations
   const Results&   m_results;     // the match_results being used.
   OutputIterator   m_out;         // where to send output.
   ForwardIter      m_position;  // format string, current position
   ForwardIter      m_end;       // format string end
   match_flag_type  m_flags;      // format flags to use
   output_state     m_state;      // what to do with the next character
   output_state     m_restore_state;  // what state to restore to.
   bool             m_have_conditional; // we are parsing a conditional
private:
   basic_regex_formatter(const basic_regex_formatter&);
   basic_regex_formatter& operator=(const basic_regex_formatter&);
};

template <class OutputIterator, class Results, class traits, class ForwardIter>
OutputIterator basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::format(ForwardIter p1, ForwardIter p2, match_flag_type f)
{
   m_position = p1;
   m_end = p2;
   m_flags = f;
   format_all();
   return m_out;
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::format_all()
{
   // over and over:
   while(m_position != m_end)
   {
      switch(*m_position)
      {
      case '&':
         if(m_flags & ::boost::regex_constants::format_sed)
         {
            ++m_position;
            put(m_results[0]);
            break;
         }
         put(*m_position++);
         break;
      case '\\':
         format_escape();
         break;
      case '(':
         if(m_flags & boost::regex_constants::format_all)
         {
            ++m_position;
            bool have_conditional = m_have_conditional;
            m_have_conditional = false;
            format_until_scope_end();
            m_have_conditional = have_conditional;
            if(m_position == m_end)
               return;
            BOOST_ASSERT(*m_position == static_cast<char_type>(')'));
            ++m_position;  // skip the closing ')'
            break;
         }
         put(*m_position);
         ++m_position;
         break;
      case ')':
         if(m_flags & boost::regex_constants::format_all)
         {
            return;
         }
         put(*m_position);
         ++m_position;
         break;
      case ':':
         if((m_flags & boost::regex_constants::format_all) && m_have_conditional)
         {
            return;
         }
         put(*m_position);
         ++m_position;
         break;
      case '?':
         if(m_flags & boost::regex_constants::format_all)
         {
            ++m_position;
            format_conditional();
            break;
         }
         put(*m_position);
         ++m_position;
         break;
      case '$':
         if((m_flags & format_sed) == 0)
         {
            format_perl();
            break;
         }
         // fall through, not a special character:
      default:
         put(*m_position);
         ++m_position;
         break;
      }
   }
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::format_perl()
{
   //
   // On entry *m_position points to a '$' character
   // output the information that goes with it:
   //
   BOOST_ASSERT(*m_position == '$');
   //
   // see if this is a trailing '$':
   //
   if(++m_position == m_end)
   {
      --m_position;
      put(*m_position);
      ++m_position;
      return;
   }
   //
   // OK find out what kind it is:
   //
   bool have_brace = false;
   ForwardIter save_position = m_position;
   switch(*m_position)
   {
   case '&':
      ++m_position;
      put(this->m_results[0]);
      break;
   case '`':
      ++m_position;
      put(this->m_results.prefix());
      break;
   case '\'':
      ++m_position;
      put(this->m_results.suffix());
      break;
   case '$':
      put(*m_position++);
      break;
   case '+':
      if((++m_position != m_end) && (*m_position == '{'))
      {
         ForwardIter base = ++m_position;
         while((m_position != m_end) && (*m_position != '}')) ++m_position;
         if(m_position != m_end)
         {
            // Named sub-expression:
            put(get_named_sub(base, m_position));
            ++m_position;
            break;
         }
         else
         {
            m_position = --base;
         }
      }
      put((this->m_results)[this->m_results.size() > 1 ? this->m_results.size() - 1 : 1]);
      break;
   case '{':
      have_brace = true;
      ++m_position;
      // fall through....
   default:
      // see if we have a number:
      {
         std::ptrdiff_t len = ::boost::re_detail::distance(m_position, m_end);
         //len = (std::min)(static_cast<std::ptrdiff_t>(2), len);
         int v = this->toi(m_position, m_position + len, 10);
         if((v < 0) || (have_brace && ((m_position == m_end) || (*m_position != '}'))))
         {
            // Look for a Perl-5.10 verb:
            if(!handle_perl_verb(have_brace))
            {
               // leave the $ as is, and carry on:
               m_position = --save_position;
               put(*m_position);
               ++m_position;
            }
            break;
         }
         // otherwise output sub v:
         put(this->m_results[v]);
         if(have_brace)
            ++m_position;
      }
   }
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
bool basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::handle_perl_verb(bool have_brace)
{
   // 
   // We may have a capitalised string containing a Perl action:
   //
   static const char_type MATCH[] = { 'M', 'A', 'T', 'C', 'H' };
   static const char_type PREMATCH[] = { 'P', 'R', 'E', 'M', 'A', 'T', 'C', 'H' };
   static const char_type POSTMATCH[] = { 'P', 'O', 'S', 'T', 'M', 'A', 'T', 'C', 'H' };
   static const char_type LAST_PAREN_MATCH[] = { 'L', 'A', 'S', 'T', '_', 'P', 'A', 'R', 'E', 'N', '_', 'M', 'A', 'T', 'C', 'H' };
   static const char_type LAST_SUBMATCH_RESULT[] = { 'L', 'A', 'S', 'T', '_', 'S', 'U', 'B', 'M', 'A', 'T', 'C', 'H', '_', 'R', 'E', 'S', 'U', 'L', 'T' };
   static const char_type LAST_SUBMATCH_RESULT_ALT[] = { '^', 'N' };

   if(m_position == m_end)
      return false;
   if(have_brace && (*m_position == '^'))
      ++m_position;

   int max_len = m_end - m_position;

   if((max_len >= 5) && std::equal(m_position, m_position + 5, MATCH))
   {
      m_position += 5;
      if(have_brace)
      {
         if((m_position != m_end) && (*m_position == '}'))
            ++m_position;
         else
         {
            m_position -= 5;
            return false;
         }
      }
      put(this->m_results[0]);
      return true;
   }
   if((max_len >= 8) && std::equal(m_position, m_position + 8, PREMATCH))
   {
      m_position += 8;
      if(have_brace)
      {
         if((m_position != m_end) && (*m_position == '}'))
            ++m_position;
         else
         {
            m_position -= 8;
            return false;
         }
      }
      put(this->m_results.prefix());
      return true;
   }
   if((max_len >= 9) && std::equal(m_position, m_position + 9, POSTMATCH))
   {
      m_position += 9;
      if(have_brace)
      {
         if((m_position != m_end) && (*m_position == '}'))
            ++m_position;
         else
         {
            m_position -= 9;
            return false;
         }
      }
      put(this->m_results.suffix());
      return true;
   }
   if((max_len >= 16) && std::equal(m_position, m_position + 16, LAST_PAREN_MATCH))
   {
      m_position += 16;
      if(have_brace)
      {
         if((m_position != m_end) && (*m_position == '}'))
            ++m_position;
         else
         {
            m_position -= 16;
            return false;
         }
      }
      put((this->m_results)[this->m_results.size() > 1 ? this->m_results.size() - 1 : 1]);
      return true;
   }
   if((max_len >= 20) && std::equal(m_position, m_position + 20, LAST_SUBMATCH_RESULT))
   {
      m_position += 20;
      if(have_brace)
      {
         if((m_position != m_end) && (*m_position == '}'))
            ++m_position;
         else
         {
            m_position -= 20;
            return false;
         }
      }
      put(this->m_results.get_last_closed_paren());
      return true;
   }
   if((max_len >= 2) && std::equal(m_position, m_position + 2, LAST_SUBMATCH_RESULT_ALT))
   {
      m_position += 2;
      if(have_brace)
      {
         if((m_position != m_end) && (*m_position == '}'))
            ++m_position;
         else
         {
            m_position -= 2;
            return false;
         }
      }
      put(this->m_results.get_last_closed_paren());
      return true;
   }
   return false;
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::format_escape()
{
   // skip the escape and check for trailing escape:
   if(++m_position == m_end)
   {
      put(static_cast<char_type>('\\'));
      return;
   }
   // now switch on the escape type:
   switch(*m_position)
   {
   case 'a':
      put(static_cast<char_type>('\a'));
      ++m_position;
      break;
   case 'f':
      put(static_cast<char_type>('\f'));
      ++m_position;
      break;
   case 'n':
      put(static_cast<char_type>('\n'));
      ++m_position;
      break;
   case 'r':
      put(static_cast<char_type>('\r'));
      ++m_position;
      break;
   case 't':
      put(static_cast<char_type>('\t'));
      ++m_position;
      break;
   case 'v':
      put(static_cast<char_type>('\v'));
      ++m_position;
      break;
   case 'x':
      if(++m_position == m_end)
      {
         put(static_cast<char_type>('x'));
         return;
      }
      // maybe have \x{ddd}
      if(*m_position == static_cast<char_type>('{'))
      {
         ++m_position;
         int val = this->toi(m_position, m_end, 16);
         if(val < 0)
         {
            // invalid value treat everything as literals:
            put(static_cast<char_type>('x'));
            put(static_cast<char_type>('{'));
            return;
         }
         if((m_position == m_end) || (*m_position != static_cast<char_type>('}')))
         {
            --m_position;
            while(*m_position != static_cast<char_type>('\\'))
               --m_position;
            ++m_position;
            put(*m_position++);
            return;
         }
         ++m_position;
         put(static_cast<char_type>(val));
         return;
      }
      else
      {
         std::ptrdiff_t len = ::boost::re_detail::distance(m_position, m_end);
         len = (std::min)(static_cast<std::ptrdiff_t>(2), len);
         int val = this->toi(m_position, m_position + len, 16);
         if(val < 0)
         {
            --m_position;
            put(*m_position++);
            return;
         }
         put(static_cast<char_type>(val));
      }
      break;
   case 'c':
      if(++m_position == m_end)
      {
         --m_position;
         put(*m_position++);
         return;
      }
      put(static_cast<char_type>(*m_position++ % 32));
      break;
   case 'e':
      put(static_cast<char_type>(27));
      ++m_position;
      break;
   default:
      // see if we have a perl specific escape:
      if((m_flags & boost::regex_constants::format_sed) == 0)
      {
         bool breakout = false;
         switch(*m_position)
         {
         case 'l':
            ++m_position;
            m_restore_state = m_state;
            m_state = output_next_lower;
            breakout = true;
            break;
         case 'L':
            ++m_position;
            m_state = output_lower;
            breakout = true;
            break;
         case 'u':
            ++m_position;
            m_restore_state = m_state;
            m_state = output_next_upper;
            breakout = true;
            break;
         case 'U':
            ++m_position;
            m_state = output_upper;
            breakout = true;
            break;
         case 'E':
            ++m_position;
            m_state = output_copy;
            breakout = true;
            break;
         }
         if(breakout)
            break;
      }
      // see if we have a \n sed style backreference:
      std::ptrdiff_t len = ::boost::re_detail::distance(m_position, m_end);
      len = (std::min)(static_cast<std::ptrdiff_t>(1), len);
      int v = this->toi(m_position, m_position+len, 10);
      if((v > 0) || ((v == 0) && (m_flags & ::boost::regex_constants::format_sed)))
      {
         put(m_results[v]);
         break;
      }
      else if(v == 0)
      {
         // octal ecape sequence:
         --m_position;
         len = ::boost::re_detail::distance(m_position, m_end);
         len = (std::min)(static_cast<std::ptrdiff_t>(4), len);
         v = this->toi(m_position, m_position + len, 8);
         BOOST_ASSERT(v >= 0);
         put(static_cast<char_type>(v));
         break;
      }
      // Otherwise output the character "as is":
      put(*m_position++);
      break;
   }
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::format_conditional()
{
   if(m_position == m_end)
   {
      // oops trailing '?':
      put(static_cast<char_type>('?'));
      return;
   }
   int v;
   if(*m_position == '{')
   {
      ForwardIter base = m_position;
      ++m_position;
      v = this->toi(m_position, m_end, 10);
      if(v < 0)
      {
         // Try a named subexpression:
         while((m_position != m_end) && (*m_position != '}'))
            ++m_position;
         v = this->get_named_sub_index(base + 1, m_position);
      }
      if((v < 0) || (*m_position != '}'))
      {
         m_position = base;
         // oops trailing '?':
         put(static_cast<char_type>('?'));
         return;
      }
      // Skip trailing '}':
      ++m_position;
   }
   else
   {
      std::ptrdiff_t len = ::boost::re_detail::distance(m_position, m_end);
      len = (std::min)(static_cast<std::ptrdiff_t>(2), len);
      v = this->toi(m_position, m_position + len, 10);
   }
   if(v < 0)
   {
      // oops not a number:
      put(static_cast<char_type>('?'));
      return;
   }

   // output varies depending upon whether sub-expression v matched or not:
   if(m_results[v].matched)
   {
      m_have_conditional = true;
      format_all();
      m_have_conditional = false;
      if((m_position != m_end) && (*m_position == static_cast<char_type>(':')))
      {
         // skip the ':':
         ++m_position;
         // save output state, then turn it off:
         output_state saved_state = m_state;
         m_state = output_none;
         // format the rest of this scope:
         format_until_scope_end();
         // restore output state:
         m_state = saved_state;
      }
   }
   else
   {
      // save output state, then turn it off:
      output_state saved_state = m_state;
      m_state = output_none;
      // format until ':' or ')':
      m_have_conditional = true;
      format_all();
      m_have_conditional = false;
      // restore state:
      m_state = saved_state;
      if((m_position != m_end) && (*m_position == static_cast<char_type>(':')))
      {
         // skip the ':':
         ++m_position;
         // format the rest of this scope:
         format_until_scope_end();
      }
   }
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::format_until_scope_end()
{
   do
   {
      format_all();
      if((m_position == m_end) || (*m_position == static_cast<char_type>(')')))
         return;
      put(*m_position++);
   }while(m_position != m_end);
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::put(char_type c)
{
   // write a single character to output
   // according to which case translation mode we are in:
   switch(this->m_state)
   {
   case output_none:
      return;
   case output_next_lower:
      c = m_traits.tolower(c);
      this->m_state = m_restore_state;
      break;
   case output_next_upper:
      c = m_traits.toupper(c);
      this->m_state = m_restore_state;
      break;
   case output_lower:
      c = m_traits.tolower(c);
      break;
   case output_upper:
      c = m_traits.toupper(c);
      break;
   default:
      break;
   }
   *m_out = c;
   ++m_out;
}

template <class OutputIterator, class Results, class traits, class ForwardIter>
void basic_regex_formatter<OutputIterator, Results, traits, ForwardIter>::put(const sub_match_type& sub)
{
   typedef typename sub_match_type::iterator iterator_type;
   iterator_type i = sub.first;
   while(i != sub.second)
   {
      put(*i);
      ++i;
   }
}

template <class S>
class string_out_iterator
#ifndef BOOST_NO_STD_ITERATOR
   : public std::iterator<std::output_iterator_tag, typename S::value_type>
#endif
{
   S* out;
public:
   string_out_iterator(S& s) : out(&s) {}
   string_out_iterator& operator++() { return *this; }
   string_out_iterator& operator++(int) { return *this; }
   string_out_iterator& operator*() { return *this; }
   string_out_iterator& operator=(typename S::value_type v) 
   { 
      out->append(1, v); 
      return *this; 
   }

#ifdef BOOST_NO_STD_ITERATOR
   typedef std::ptrdiff_t difference_type;
   typedef typename S::value_type value_type;
   typedef value_type* pointer;
   typedef value_type& reference;
   typedef std::output_iterator_tag iterator_category;
#endif
};

template <class OutputIterator, class Iterator, class Alloc, class ForwardIter, class traits>
OutputIterator regex_format_imp(OutputIterator out,
                          const match_results<Iterator, Alloc>& m,
                          ForwardIter p1, ForwardIter p2,
                          match_flag_type flags,
                          const traits& t
                         )
{
   if(flags & regex_constants::format_literal)
   {
      return re_detail::copy(p1, p2, out);
   }

   re_detail::basic_regex_formatter<
      OutputIterator, 
      match_results<Iterator, Alloc>, 
      traits, ForwardIter> f(out, m, t);
   return f.format(p1, p2, flags);
}

#ifndef BOOST_NO_SFINAE

BOOST_MPL_HAS_XXX_TRAIT_DEF(const_iterator)

struct any_type { any_type(...); };
typedef char no_type;
typedef char (&unary_type)[2];
typedef char (&binary_type)[3];
typedef char (&ternary_type)[4];

no_type check_is_formatter(unary_type, binary_type, ternary_type);
template<typename T>
unary_type check_is_formatter(T const &, binary_type, ternary_type);
template<typename T>
binary_type check_is_formatter(unary_type, T const &, ternary_type);
template<typename T, typename U>
binary_type check_is_formatter(T const &, U const &, ternary_type);
template<typename T>
ternary_type check_is_formatter(unary_type, binary_type, T const &);
template<typename T, typename U>
ternary_type check_is_formatter(T const &, binary_type, U const &);
template<typename T, typename U>
ternary_type check_is_formatter(unary_type, T const &, U const &);
template<typename T, typename U, typename V>
ternary_type check_is_formatter(T const &, U const &, V const &);

struct unary_binary_ternary
{
    typedef unary_type (*unary_fun)(any_type);
    typedef binary_type (*binary_fun)(any_type, any_type);
    typedef ternary_type (*ternary_fun)(any_type, any_type, any_type);
    operator unary_fun();
    operator binary_fun();
    operator ternary_fun();
};

template<typename Formatter, bool IsFunction = boost::is_function<Formatter>::value>
struct formatter_wrapper
  : Formatter
  , unary_binary_ternary
{
   formatter_wrapper(){}
};

template<typename Formatter>
struct formatter_wrapper<Formatter, true>
  : unary_binary_ternary
{
    operator Formatter *();
};

template<typename Formatter>
struct formatter_wrapper<Formatter *, false>
  : unary_binary_ternary
{
    operator Formatter *();
};

template <class F, class M, class O>
struct format_traits_imp
{
private:
   //
   // F must be a pointer, a function, or a class with a function call operator:
   //
   BOOST_STATIC_ASSERT((::boost::is_pointer<F>::value || ::boost::is_function<F>::value || ::boost::is_class<F>::value));
   static formatter_wrapper<F> f;
   static M m;
   static O out;
   static boost::regex_constants::match_flag_type flags;
public:
   BOOST_STATIC_CONSTANT(int, value = sizeof(check_is_formatter(f(m), f(m, out), f(m, out, flags))));
};

template <class F, class M, class O>
struct format_traits
{
public:
   // 
   // Type is mpl::int_<N> where N is one of:
   //
   // 0 : F is a pointer to a presumably null-terminated string.
   // 1 : F is a character-container such as a std::string.
   // 2 : F is a Unary Functor.
   // 3 : F is a Binary Functor.
   // 4 : F is a Ternary Functor.
   //
   typedef typename boost::mpl::if_<
      boost::mpl::and_<boost::is_pointer<F>, boost::mpl::not_<boost::is_function<typename boost::remove_pointer<F>::type> > >,
      boost::mpl::int_<0>,
      typename boost::mpl::if_<
         has_const_iterator<F>,
         boost::mpl::int_<1>,
         boost::mpl::int_<format_traits_imp<F, M, O>::value>
      >::type
   >::type type;
   //
   // This static assertion will fail if the functor passed does not accept
   // the same type of arguments passed.
   //
   BOOST_STATIC_ASSERT( boost::is_class<F>::value && !has_const_iterator<F>::value ? (type::value > 1) : true);
};

#else // BOOST_NO_SFINAE

template <class F, class M, class O>
struct format_traits
{
public:
   // 
   // Type is mpl::int_<N> where N is one of:
   //
   // 0 : F is a pointer to a presumably null-terminated string.
   // 1 : F is a character-container such as a std::string.
   //
   // Other options such as F being a Functor are not supported without
   // SFINAE support.
   //
   typedef typename boost::mpl::if_<
      boost::is_pointer<F>,
      boost::mpl::int_<0>,
      boost::mpl::int_<1>
   >::type type;
};

#endif // BOOST_NO_SFINAE

template <class Base, class Match>
struct format_functor3
{
   format_functor3(Base b) : func(b) {}
   template <class OutputIter>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type f)
   {
      return func(m, i, f);
   }
   template <class OutputIter, class Traits>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type f, const Traits&)
   {
      return (*this)(m, i, f);
   }
private:
   Base func;
   format_functor3(const format_functor3&);
   format_functor3& operator=(const format_functor3&);
};

template <class Base, class Match>
struct format_functor2
{
   format_functor2(Base b) : func(b) {}
   template <class OutputIter>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type /*f*/)
   {
      return func(m, i);
   }
   template <class OutputIter, class Traits>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type f, const Traits&)
   {
      return (*this)(m, i, f);
   }
private:
   Base func;
   format_functor2(const format_functor2&);
   format_functor2& operator=(const format_functor2&);
};

template <class Base, class Match>
struct format_functor1
{
   format_functor1(Base b) : func(b) {}

   template <class S, class OutputIter>
   OutputIter do_format_string(const S& s, OutputIter i)
   {
      return re_detail::copy(s.begin(), s.end(), i);
   }
   template <class S, class OutputIter>
   inline OutputIter do_format_string(const S* s, OutputIter i)
   {
      while(s && *s)
      {
         *i = *s;
         ++i;
         ++s;
      }
      return i;
   }
   template <class OutputIter>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type /*f*/)
   {
      return do_format_string(func(m), i);
   }
   template <class OutputIter, class Traits>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type f, const Traits&)
   {
      return (*this)(m, i, f);
   }
private:
   Base func;
   format_functor1(const format_functor1&);
   format_functor1& operator=(const format_functor1&);
};

template <class charT, class Match, class Traits>
struct format_functor_c_string
{
   format_functor_c_string(const charT* ps) : func(ps) {}

   template <class OutputIter>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type f, const Traits& t = Traits())
   {
      typedef typename Match::char_type char_type;
      const charT* end = func;
      while(*end) ++end;
      return regex_format_imp(i, m, func, end, f, t);
   }
private:
   const charT* func;
   format_functor_c_string(const format_functor_c_string&);
   format_functor_c_string& operator=(const format_functor_c_string&);
};

template <class Container, class Match, class Traits>
struct format_functor_container
{
   format_functor_container(const Container& c) : func(c) {}

   template <class OutputIter>
   OutputIter operator()(const Match& m, OutputIter i, boost::regex_constants::match_flag_type f, const Traits& t = Traits())
   {
      typedef typename Match::char_type char_type;
      return re_detail::regex_format_imp(i, m, func.begin(), func.end(), f, t);
   }
private:
   const Container& func;
   format_functor_container(const format_functor_container&);
   format_functor_container& operator=(const format_functor_container&);
};

template <class Func, class Match, class OutputIterator, class Traits = re_detail::trivial_format_traits<typename Match::char_type> >
struct compute_functor_type
{
   typedef typename format_traits<Func, Match, OutputIterator>::type tag;
   typedef typename boost::remove_cv< typename boost::remove_pointer<Func>::type>::type maybe_char_type;

   typedef typename mpl::if_<
      ::boost::is_same<tag, mpl::int_<0> >, format_functor_c_string<maybe_char_type, Match, Traits>,
      typename mpl::if_<
         ::boost::is_same<tag, mpl::int_<1> >, format_functor_container<Func, Match, Traits>,
         typename mpl::if_<
            ::boost::is_same<tag, mpl::int_<2> >, format_functor1<Func, Match>,
            typename mpl::if_<
               ::boost::is_same<tag, mpl::int_<3> >, format_functor2<Func, Match>, 
               format_functor3<Func, Match>
            >::type
         >::type
      >::type
   >::type type;
};

} // namespace re_detail

template <class OutputIterator, class Iterator, class Allocator, class Functor>
inline OutputIterator regex_format(OutputIterator out,
                          const match_results<Iterator, Allocator>& m,
                          Functor fmt,
                          match_flag_type flags = format_all
                         )
{
   return m.format(out, fmt, flags);
}

template <class Iterator, class Allocator, class Functor>
inline std::basic_string<typename match_results<Iterator, Allocator>::char_type> regex_format(const match_results<Iterator, Allocator>& m, 
                                      Functor fmt, 
                                      match_flag_type flags = format_all)
{
   return m.format(fmt, flags);
}

#ifdef BOOST_MSVC
#pragma warning(push)
#pragma warning(disable: 4103)
#endif
#ifdef BOOST_HAS_ABI_HEADERS
#  include BOOST_ABI_SUFFIX
#endif
#ifdef BOOST_MSVC
#pragma warning(pop)
#endif

} // namespace boost

#endif  // BOOST_REGEX_FORMAT_HPP