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
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
|
.. highlightlang:: c
.. _unicodeobjects:
Unicode Objects and Codecs
--------------------------
.. sectionauthor:: Marc-Andre Lemburg <mal@lemburg.com>
.. sectionauthor:: Georg Brandl <georg@python.org>
Unicode Objects
^^^^^^^^^^^^^^^
Since the implementation of :pep:`393` in Python 3.3, Unicode objects internally
use a variety of representations, in order to allow handling the complete range
of Unicode characters while staying memory efficient. There are special cases
for strings where all code points are below 128, 256, or 65536; otherwise, code
points must be below 1114112 (which is the full Unicode range).
:c:type:`Py_UNICODE*` and UTF-8 representations are created on demand and cached
in the Unicode object. The :c:type:`Py_UNICODE*` representation is deprecated
and inefficient; it should be avoided in performance- or memory-sensitive
situations.
Due to the transition between the old APIs and the new APIs, unicode objects
can internally be in two states depending on how they were created:
* "canonical" unicode objects are all objects created by a non-deprecated
unicode API. They use the most efficient representation allowed by the
implementation.
* "legacy" unicode objects have been created through one of the deprecated
APIs (typically :c:func:`PyUnicode_FromUnicode`) and only bear the
:c:type:`Py_UNICODE*` representation; you will have to call
:c:func:`PyUnicode_READY` on them before calling any other API.
Unicode Type
""""""""""""
These are the basic Unicode object types used for the Unicode implementation in
Python:
.. c:type:: Py_UCS4
Py_UCS2
Py_UCS1
These types are typedefs for unsigned integer types wide enough to contain
characters of 32 bits, 16 bits and 8 bits, respectively. When dealing with
single Unicode characters, use :c:type:`Py_UCS4`.
.. versionadded:: 3.3
.. c:type:: Py_UNICODE
This is a typedef of :c:type:`wchar_t`, which is a 16-bit type or 32-bit type
depending on the platform.
.. versionchanged:: 3.3
In previous versions, this was a 16-bit type or a 32-bit type depending on
whether you selected a "narrow" or "wide" Unicode version of Python at
build time.
.. c:type:: PyASCIIObject
PyCompactUnicodeObject
PyUnicodeObject
These subtypes of :c:type:`PyObject` represent a Python Unicode object. In
almost all cases, they shouldn't be used directly, since all API functions
that deal with Unicode objects take and return :c:type:`PyObject` pointers.
.. versionadded:: 3.3
.. c:var:: PyTypeObject PyUnicode_Type
This instance of :c:type:`PyTypeObject` represents the Python Unicode type. It
is exposed to Python code as ``str``.
The following APIs are really C macros and can be used to do fast checks and to
access internal read-only data of Unicode objects:
.. c:function:: int PyUnicode_Check(PyObject *o)
Return true if the object *o* is a Unicode object or an instance of a Unicode
subtype.
.. c:function:: int PyUnicode_CheckExact(PyObject *o)
Return true if the object *o* is a Unicode object, but not an instance of a
subtype.
.. c:function:: int PyUnicode_READY(PyObject *o)
Ensure the string object *o* is in the "canonical" representation. This is
required before using any of the access macros described below.
.. XXX expand on when it is not required
Returns 0 on success and -1 with an exception set on failure, which in
particular happens if memory allocation fails.
.. versionadded:: 3.3
.. c:function:: Py_ssize_t PyUnicode_GET_LENGTH(PyObject *o)
Return the length of the Unicode string, in code points. *o* has to be a
Unicode object in the "canonical" representation (not checked).
.. versionadded:: 3.3
.. c:function:: Py_UCS1* PyUnicode_1BYTE_DATA(PyObject *o)
Py_UCS2* PyUnicode_2BYTE_DATA(PyObject *o)
Py_UCS4* PyUnicode_4BYTE_DATA(PyObject *o)
Return a pointer to the canonical representation cast to UCS1, UCS2 or UCS4
integer types for direct character access. No checks are performed if the
canonical representation has the correct character size; use
:c:func:`PyUnicode_KIND` to select the right macro. Make sure
:c:func:`PyUnicode_READY` has been called before accessing this.
.. versionadded:: 3.3
.. c:macro:: PyUnicode_WCHAR_KIND
PyUnicode_1BYTE_KIND
PyUnicode_2BYTE_KIND
PyUnicode_4BYTE_KIND
Return values of the :c:func:`PyUnicode_KIND` macro.
.. versionadded:: 3.3
.. c:function:: int PyUnicode_KIND(PyObject *o)
Return one of the PyUnicode kind constants (see above) that indicate how many
bytes per character this Unicode object uses to store its data. *o* has to
be a Unicode object in the "canonical" representation (not checked).
.. XXX document "0" return value?
.. versionadded:: 3.3
.. c:function:: void* PyUnicode_DATA(PyObject *o)
Return a void pointer to the raw unicode buffer. *o* has to be a Unicode
object in the "canonical" representation (not checked).
.. versionadded:: 3.3
.. c:function:: void PyUnicode_WRITE(int kind, void *data, Py_ssize_t index, \
Py_UCS4 value)
Write into a canonical representation *data* (as obtained with
:c:func:`PyUnicode_DATA`). This macro does not do any sanity checks and is
intended for usage in loops. The caller should cache the *kind* value and
*data* pointer as obtained from other macro calls. *index* is the index in
the string (starts at 0) and *value* is the new code point value which should
be written to that location.
.. versionadded:: 3.3
.. c:function:: Py_UCS4 PyUnicode_READ(int kind, void *data, Py_ssize_t index)
Read a code point from a canonical representation *data* (as obtained with
:c:func:`PyUnicode_DATA`). No checks or ready calls are performed.
.. versionadded:: 3.3
.. c:function:: Py_UCS4 PyUnicode_READ_CHAR(PyObject *o, Py_ssize_t index)
Read a character from a Unicode object *o*, which must be in the "canonical"
representation. This is less efficient than :c:func:`PyUnicode_READ` if you
do multiple consecutive reads.
.. versionadded:: 3.3
.. c:function:: PyUnicode_MAX_CHAR_VALUE(PyObject *o)
Return the maximum code point that is suitable for creating another string
based on *o*, which must be in the "canonical" representation. This is
always an approximation but more efficient than iterating over the string.
.. versionadded:: 3.3
.. c:function:: int PyUnicode_ClearFreeList()
Clear the free list. Return the total number of freed items.
.. c:function:: Py_ssize_t PyUnicode_GET_SIZE(PyObject *o)
Return the size of the deprecated :c:type:`Py_UNICODE` representation, in
code units (this includes surrogate pairs as 2 units). *o* has to be a
Unicode object (not checked).
.. deprecated-removed:: 3.3 4.0
Part of the old-style Unicode API, please migrate to using
:c:func:`PyUnicode_GET_LENGTH`.
.. c:function:: Py_ssize_t PyUnicode_GET_DATA_SIZE(PyObject *o)
Return the size of the deprecated :c:type:`Py_UNICODE` representation in
bytes. *o* has to be a Unicode object (not checked).
.. deprecated-removed:: 3.3 4.0
Part of the old-style Unicode API, please migrate to using
:c:func:`PyUnicode_GET_LENGTH`.
.. c:function:: Py_UNICODE* PyUnicode_AS_UNICODE(PyObject *o)
const char* PyUnicode_AS_DATA(PyObject *o)
Return a pointer to a :c:type:`Py_UNICODE` representation of the object. The
``AS_DATA`` form casts the pointer to :c:type:`const char *`. *o* has to be
a Unicode object (not checked).
.. versionchanged:: 3.3
This macro is now inefficient -- because in many cases the
:c:type:`Py_UNICODE` representation does not exist and needs to be created
-- and can fail (return *NULL* with an exception set). Try to port the
code to use the new :c:func:`PyUnicode_nBYTE_DATA` macros or use
:c:func:`PyUnicode_WRITE` or :c:func:`PyUnicode_READ`.
.. deprecated-removed:: 3.3 4.0
Part of the old-style Unicode API, please migrate to using the
:c:func:`PyUnicode_nBYTE_DATA` family of macros.
Unicode Character Properties
""""""""""""""""""""""""""""
Unicode provides many different character properties. The most often needed ones
are available through these macros which are mapped to C functions depending on
the Python configuration.
.. c:function:: int Py_UNICODE_ISSPACE(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a whitespace character.
.. c:function:: int Py_UNICODE_ISLOWER(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a lowercase character.
.. c:function:: int Py_UNICODE_ISUPPER(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is an uppercase character.
.. c:function:: int Py_UNICODE_ISTITLE(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a titlecase character.
.. c:function:: int Py_UNICODE_ISLINEBREAK(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a linebreak character.
.. c:function:: int Py_UNICODE_ISDECIMAL(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a decimal character.
.. c:function:: int Py_UNICODE_ISDIGIT(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a digit character.
.. c:function:: int Py_UNICODE_ISNUMERIC(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a numeric character.
.. c:function:: int Py_UNICODE_ISALPHA(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is an alphabetic character.
.. c:function:: int Py_UNICODE_ISALNUM(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is an alphanumeric character.
.. c:function:: int Py_UNICODE_ISPRINTABLE(Py_UNICODE ch)
Return 1 or 0 depending on whether *ch* is a printable character.
Nonprintable characters are those characters defined in the Unicode character
database as "Other" or "Separator", excepting the ASCII space (0x20) which is
considered printable. (Note that printable characters in this context are
those which should not be escaped when :func:`repr` is invoked on a string.
It has no bearing on the handling of strings written to :data:`sys.stdout` or
:data:`sys.stderr`.)
These APIs can be used for fast direct character conversions:
.. c:function:: Py_UNICODE Py_UNICODE_TOLOWER(Py_UNICODE ch)
Return the character *ch* converted to lower case.
.. c:function:: Py_UNICODE Py_UNICODE_TOUPPER(Py_UNICODE ch)
Return the character *ch* converted to upper case.
.. c:function:: Py_UNICODE Py_UNICODE_TOTITLE(Py_UNICODE ch)
Return the character *ch* converted to title case.
.. c:function:: int Py_UNICODE_TODECIMAL(Py_UNICODE ch)
Return the character *ch* converted to a decimal positive integer. Return
``-1`` if this is not possible. This macro does not raise exceptions.
.. c:function:: int Py_UNICODE_TODIGIT(Py_UNICODE ch)
Return the character *ch* converted to a single digit integer. Return ``-1`` if
this is not possible. This macro does not raise exceptions.
.. c:function:: double Py_UNICODE_TONUMERIC(Py_UNICODE ch)
Return the character *ch* converted to a double. Return ``-1.0`` if this is not
possible. This macro does not raise exceptions.
These APIs can be used to work with surrogates:
.. c:macro:: Py_UNICODE_IS_SURROGATE(ch)
Check if *ch* is a surrogate (``0xD800 <= ch <= 0xDFFF``).
.. c:macro:: Py_UNICODE_IS_HIGH_SURROGATE(ch)
Check if *ch* is an high surrogate (``0xD800 <= ch <= 0xDBFF``).
.. c:macro:: Py_UNICODE_IS_LOW_SURROGATE(ch)
Check if *ch* is a low surrogate (``0xDC00 <= ch <= 0xDFFF``).
.. c:macro:: Py_UNICODE_JOIN_SURROGATES(high, low)
Join two surrogate characters and return a single Py_UCS4 value.
*high* and *low* are respectively the leading and trailing surrogates in a
surrogate pair.
Creating and accessing Unicode strings
""""""""""""""""""""""""""""""""""""""
To create Unicode objects and access their basic sequence properties, use these
APIs:
.. c:function:: PyObject* PyUnicode_New(Py_ssize_t size, Py_UCS4 maxchar)
Create a new Unicode object. *maxchar* should be the true maximum code point
to be placed in the string. As an approximation, it can be rounded up to the
nearest value in the sequence 127, 255, 65535, 1114111.
This is the recommended way to allocate a new Unicode object. Objects
created using this function are not resizable.
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_FromKindAndData(int kind, const void *buffer, \
Py_ssize_t size)
Create a new Unicode object with the given *kind* (possible values are
:c:macro:`PyUnicode_1BYTE_KIND` etc., as returned by
:c:func:`PyUnicode_KIND`). The *buffer* must point to an array of *size*
units of 1, 2 or 4 bytes per character, as given by the kind.
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_FromStringAndSize(const char *u, Py_ssize_t size)
Create a Unicode object from the char buffer *u*. The bytes will be
interpreted as being UTF-8 encoded. The buffer is copied into the new
object. If the buffer is not *NULL*, the return value might be a shared
object, i.e. modification of the data is not allowed.
If *u* is *NULL*, this function behaves like :c:func:`PyUnicode_FromUnicode`
with the buffer set to *NULL*. This usage is deprecated in favor of
:c:func:`PyUnicode_New`.
.. c:function:: PyObject *PyUnicode_FromString(const char *u)
Create a Unicode object from an UTF-8 encoded null-terminated char buffer
*u*.
.. c:function:: PyObject* PyUnicode_FromFormat(const char *format, ...)
Take a C :c:func:`printf`\ -style *format* string and a variable number of
arguments, calculate the size of the resulting Python unicode string and return
a string with the values formatted into it. The variable arguments must be C
types and must correspond exactly to the format characters in the *format*
ASCII-encoded string. The following format characters are allowed:
.. % This should be exactly the same as the table in PyErr_Format.
.. % The descriptions for %zd and %zu are wrong, but the truth is complicated
.. % because not all compilers support the %z width modifier -- we fake it
.. % when necessary via interpolating PY_FORMAT_SIZE_T.
.. % Similar comments apply to the %ll width modifier and
.. % PY_FORMAT_LONG_LONG.
+-------------------+---------------------+--------------------------------+
| Format Characters | Type | Comment |
+===================+=====================+================================+
| :attr:`%%` | *n/a* | The literal % character. |
+-------------------+---------------------+--------------------------------+
| :attr:`%c` | int | A single character, |
| | | represented as an C int. |
+-------------------+---------------------+--------------------------------+
| :attr:`%d` | int | Exactly equivalent to |
| | | ``printf("%d")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%u` | unsigned int | Exactly equivalent to |
| | | ``printf("%u")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%ld` | long | Exactly equivalent to |
| | | ``printf("%ld")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%li` | long | Exactly equivalent to |
| | | ``printf("%li")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%lu` | unsigned long | Exactly equivalent to |
| | | ``printf("%lu")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%lld` | long long | Exactly equivalent to |
| | | ``printf("%lld")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%lli` | long long | Exactly equivalent to |
| | | ``printf("%lli")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%llu` | unsigned long long | Exactly equivalent to |
| | | ``printf("%llu")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%zd` | Py_ssize_t | Exactly equivalent to |
| | | ``printf("%zd")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%zi` | Py_ssize_t | Exactly equivalent to |
| | | ``printf("%zi")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%zu` | size_t | Exactly equivalent to |
| | | ``printf("%zu")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%i` | int | Exactly equivalent to |
| | | ``printf("%i")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%x` | int | Exactly equivalent to |
| | | ``printf("%x")``. |
+-------------------+---------------------+--------------------------------+
| :attr:`%s` | char\* | A null-terminated C character |
| | | array. |
+-------------------+---------------------+--------------------------------+
| :attr:`%p` | void\* | The hex representation of a C |
| | | pointer. Mostly equivalent to |
| | | ``printf("%p")`` except that |
| | | it is guaranteed to start with |
| | | the literal ``0x`` regardless |
| | | of what the platform's |
| | | ``printf`` yields. |
+-------------------+---------------------+--------------------------------+
| :attr:`%A` | PyObject\* | The result of calling |
| | | :func:`ascii`. |
+-------------------+---------------------+--------------------------------+
| :attr:`%U` | PyObject\* | A unicode object. |
+-------------------+---------------------+--------------------------------+
| :attr:`%V` | PyObject\*, char \* | A unicode object (which may be |
| | | *NULL*) and a null-terminated |
| | | C character array as a second |
| | | parameter (which will be used, |
| | | if the first parameter is |
| | | *NULL*). |
+-------------------+---------------------+--------------------------------+
| :attr:`%S` | PyObject\* | The result of calling |
| | | :c:func:`PyObject_Str`. |
+-------------------+---------------------+--------------------------------+
| :attr:`%R` | PyObject\* | The result of calling |
| | | :c:func:`PyObject_Repr`. |
+-------------------+---------------------+--------------------------------+
An unrecognized format character causes all the rest of the format string to be
copied as-is to the result string, and any extra arguments discarded.
.. note::
The `"%lld"` and `"%llu"` format specifiers are only available
when :const:`HAVE_LONG_LONG` is defined.
.. versionchanged:: 3.2
Support for ``"%lld"`` and ``"%llu"`` added.
.. versionchanged:: 3.3
Support for ``"%li"``, ``"%lli"`` and ``"%zi"`` added.
.. c:function:: PyObject* PyUnicode_FromFormatV(const char *format, va_list vargs)
Identical to :c:func:`PyUnicode_FromFormat` except that it takes exactly two
arguments.
.. c:function:: PyObject* PyUnicode_FromEncodedObject(PyObject *obj, \
const char *encoding, const char *errors)
Coerce an encoded object *obj* to an Unicode object and return a reference with
incremented refcount.
:class:`bytes`, :class:`bytearray` and other char buffer compatible objects
are decoded according to the given *encoding* and using the error handling
defined by *errors*. Both can be *NULL* to have the interface use the default
values (see the next section for details).
All other objects, including Unicode objects, cause a :exc:`TypeError` to be
set.
The API returns *NULL* if there was an error. The caller is responsible for
decref'ing the returned objects.
.. c:function:: Py_ssize_t PyUnicode_GetLength(PyObject *unicode)
Return the length of the Unicode object, in code points.
.. versionadded:: 3.3
.. c:function:: int PyUnicode_CopyCharacters(PyObject *to, Py_ssize_t to_start, \
PyObject *to, Py_ssize_t from_start, Py_ssize_t how_many)
Copy characters from one Unicode object into another. This function performs
character conversion when necessary and falls back to :c:func:`memcpy` if
possible. Returns ``-1`` and sets an exception on error, otherwise returns
``0``.
.. versionadded:: 3.3
.. c:function:: int PyUnicode_WriteChar(PyObject *unicode, Py_ssize_t index, \
Py_UCS4 character)
Write a character to a string. The string must have been created through
:c:func:`PyUnicode_New`. Since Unicode strings are supposed to be immutable,
the string must not be shared, or have been hashed yet.
This function checks that *unicode* is a Unicode object, that the index is
not out of bounds, and that the object can be modified safely (i.e. that it
its reference count is one), in contrast to the macro version
:c:func:`PyUnicode_WRITE_CHAR`.
.. versionadded:: 3.3
.. c:function:: Py_UCS4 PyUnicode_ReadChar(PyObject *unicode, Py_ssize_t index)
Read a character from a string. This function checks that *unicode* is a
Unicode object and the index is not out of bounds, in contrast to the macro
version :c:func:`PyUnicode_READ_CHAR`.
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_Substring(PyObject *str, Py_ssize_t start, \
Py_ssize_t end)
Return a substring of *str*, from character index *start* (included) to
character index *end* (excluded). Negative indices are not supported.
.. versionadded:: 3.3
.. c:function:: Py_UCS4* PyUnicode_AsUCS4(PyObject *u, Py_UCS4 *buffer, \
Py_ssize_t buflen, int copy_null)
Copy the string *u* into a UCS4 buffer, including a null character, if
*copy_null* is set. Returns *NULL* and sets an exception on error (in
particular, a :exc:`ValueError` if *buflen* is smaller than the length of
*u*). *buffer* is returned on success.
.. versionadded:: 3.3
.. c:function:: Py_UCS4* PyUnicode_AsUCS4Copy(PyObject *u)
Copy the string *u* into a new UCS4 buffer that is allocated using
:c:func:`PyMem_Malloc`. If this fails, *NULL* is returned with a
:exc:`MemoryError` set.
.. versionadded:: 3.3
Deprecated Py_UNICODE APIs
""""""""""""""""""""""""""
.. deprecated-removed:: 3.3 4.0
These API functions are deprecated with the implementation of :pep:`393`.
Extension modules can continue using them, as they will not be removed in Python
3.x, but need to be aware that their use can now cause performance and memory hits.
.. c:function:: PyObject* PyUnicode_FromUnicode(const Py_UNICODE *u, Py_ssize_t size)
Create a Unicode object from the Py_UNICODE buffer *u* of the given size. *u*
may be *NULL* which causes the contents to be undefined. It is the user's
responsibility to fill in the needed data. The buffer is copied into the new
object.
If the buffer is not *NULL*, the return value might be a shared object.
Therefore, modification of the resulting Unicode object is only allowed when
*u* is *NULL*.
If the buffer is *NULL*, :c:func:`PyUnicode_READY` must be called once the
string content has been filled before using any of the access macros such as
:c:func:`PyUnicode_KIND`.
Please migrate to using :c:func:`PyUnicode_FromKindAndData` or
:c:func:`PyUnicode_New`.
.. c:function:: Py_UNICODE* PyUnicode_AsUnicode(PyObject *unicode)
Return a read-only pointer to the Unicode object's internal
:c:type:`Py_UNICODE` buffer, *NULL* if *unicode* is not a Unicode object.
This will create the :c:type:`Py_UNICODE` representation of the object if it
is not yet available.
Please migrate to using :c:func:`PyUnicode_AsUCS4`,
:c:func:`PyUnicode_Substring`, :c:func:`PyUnicode_ReadChar` or similar new
APIs.
.. c:function:: PyObject* PyUnicode_TransformDecimalToASCII(Py_UNICODE *s, Py_ssize_t size)
Create a Unicode object by replacing all decimal digits in
:c:type:`Py_UNICODE` buffer of the given *size* by ASCII digits 0--9
according to their decimal value. Return *NULL* if an exception occurs.
.. c:function:: Py_UNICODE* PyUnicode_AsUnicodeAndSize(PyObject *unicode, Py_ssize_t *size)
Like :c:func:`PyUnicode_AsUnicode`, but also saves the :c:func:`Py_UNICODE`
array length in *size*.
.. versionadded:: 3.3
.. c:function:: Py_UNICODE* PyUnicode_AsUnicodeCopy(PyObject *unicode)
Create a copy of a Unicode string ending with a nul character. Return *NULL*
and raise a :exc:`MemoryError` exception on memory allocation failure,
otherwise return a new allocated buffer (use :c:func:`PyMem_Free` to free the
buffer).
.. versionadded:: 3.2
Please migrate to using :c:func:`PyUnicode_AsUCS4Copy` or similar new APIs.
.. c:function:: Py_ssize_t PyUnicode_GetSize(PyObject *unicode)
Return the size of the deprecated :c:type:`Py_UNICODE` representation, in
code units (this includes surrogate pairs as 2 units).
Please migrate to using :c:func:`PyUnicode_GetLength`.
.. c:function:: PyObject* PyUnicode_FromObject(PyObject *obj)
Shortcut for ``PyUnicode_FromEncodedObject(obj, NULL, "strict")`` which is used
throughout the interpreter whenever coercion to Unicode is needed.
Locale Encoding
"""""""""""""""
The current locale encoding can be used to decode text from the operating
system.
.. c:function:: PyObject* PyUnicode_DecodeLocaleAndSize(const char *str, Py_ssize_t len, int surrogateescape)
Decode a string from the current locale encoding. The decoder is strict if
*surrogateescape* is equal to zero, otherwise it uses the
``'surrogateescape'`` error handler (:pep:`383`) to escape undecodable
bytes. If a byte sequence can be decoded as a surrogate character and
*surrogateescape* is not equal to zero, the byte sequence is escaped using
the ``'surrogateescape'`` error handler instead of being decoded. *str*
must end with a null character but cannot contain embedded null characters.
.. seealso::
Use :c:func:`PyUnicode_DecodeFSDefaultAndSize` to decode a string from
:c:data:`Py_FileSystemDefaultEncoding` (the locale encoding read at
Python startup).
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_DecodeLocale(const char *str, int surrogateescape)
Similar to :c:func:`PyUnicode_DecodeLocaleAndSize`, but compute the string
length using :c:func:`strlen`.
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_EncodeLocale(PyObject *unicode, int surrogateescape)
Encode a Unicode object to the current locale encoding. The encoder is
strict if *surrogateescape* is equal to zero, otherwise it uses the
``'surrogateescape'`` error handler (:pep:`383`). Return a :class:`bytes`
object. *str* cannot contain embedded null characters.
.. seealso::
Use :c:func:`PyUnicode_EncodeFSDefault` to encode a string to
:c:data:`Py_FileSystemDefaultEncoding` (the locale encoding read at
Python startup).
.. versionadded:: 3.3
File System Encoding
""""""""""""""""""""
To encode and decode file names and other environment strings,
:c:data:`Py_FileSystemEncoding` should be used as the encoding, and
``"surrogateescape"`` should be used as the error handler (:pep:`383`). To
encode file names during argument parsing, the ``"O&"`` converter should be
used, passing :c:func:`PyUnicode_FSConverter` as the conversion function:
.. c:function:: int PyUnicode_FSConverter(PyObject* obj, void* result)
ParseTuple converter: encode :class:`str` objects to :class:`bytes` using
:c:func:`PyUnicode_EncodeFSDefault`; :class:`bytes` objects are output as-is.
*result* must be a :c:type:`PyBytesObject*` which must be released when it is
no longer used.
.. versionadded:: 3.1
To decode file names during argument parsing, the ``"O&"`` converter should be
used, passing :c:func:`PyUnicode_FSDecoder` as the conversion function:
.. c:function:: int PyUnicode_FSDecoder(PyObject* obj, void* result)
ParseTuple converter: decode :class:`bytes` objects to :class:`str` using
:c:func:`PyUnicode_DecodeFSDefaultAndSize`; :class:`str` objects are output
as-is. *result* must be a :c:type:`PyUnicodeObject*` which must be released
when it is no longer used.
.. versionadded:: 3.2
.. c:function:: PyObject* PyUnicode_DecodeFSDefaultAndSize(const char *s, Py_ssize_t size)
Decode a string using :c:data:`Py_FileSystemDefaultEncoding` and the
``'surrogateescape'`` error handler, or ``'strict'`` on Windows.
If :c:data:`Py_FileSystemDefaultEncoding` is not set, fall back to the
locale encoding.
.. seealso::
:c:data:`Py_FileSystemDefaultEncoding` is initialized at startup from the
locale encoding and cannot be modified later. If you need to decode a
string from the current locale encoding, use
:c:func:`PyUnicode_DecodeLocaleAndSize`.
.. versionchanged:: 3.2
Use ``'strict'`` error handler on Windows.
.. c:function:: PyObject* PyUnicode_DecodeFSDefault(const char *s)
Decode a null-terminated string using :c:data:`Py_FileSystemDefaultEncoding`
and the ``'surrogateescape'`` error handler, or ``'strict'`` on Windows.
If :c:data:`Py_FileSystemDefaultEncoding` is not set, fall back to the
locale encoding.
Use :c:func:`PyUnicode_DecodeFSDefaultAndSize` if you know the string length.
.. versionchanged:: 3.2
Use ``'strict'`` error handler on Windows.
.. c:function:: PyObject* PyUnicode_EncodeFSDefault(PyObject *unicode)
Encode a Unicode object to :c:data:`Py_FileSystemDefaultEncoding` with the
``'surrogateescape'`` error handler, or ``'strict'`` on Windows, and return
:class:`bytes`.
If :c:data:`Py_FileSystemDefaultEncoding` is not set, fall back to the
locale encoding.
.. seealso::
:c:data:`Py_FileSystemDefaultEncoding` is initialized at startup from the
locale encoding and cannot be modified later. If you need to encode a
string to the current locale encoding, use
:c:func:`PyUnicode_EncodeLocale`.
.. versionadded:: 3.2
wchar_t Support
"""""""""""""""
:c:type:`wchar_t` support for platforms which support it:
.. c:function:: PyObject* PyUnicode_FromWideChar(const wchar_t *w, Py_ssize_t size)
Create a Unicode object from the :c:type:`wchar_t` buffer *w* of the given *size*.
Passing -1 as the *size* indicates that the function must itself compute the length,
using wcslen.
Return *NULL* on failure.
.. c:function:: Py_ssize_t PyUnicode_AsWideChar(PyUnicodeObject *unicode, wchar_t *w, Py_ssize_t size)
Copy the Unicode object contents into the :c:type:`wchar_t` buffer *w*. At most
*size* :c:type:`wchar_t` characters are copied (excluding a possibly trailing
0-termination character). Return the number of :c:type:`wchar_t` characters
copied or -1 in case of an error. Note that the resulting :c:type:`wchar_t`
string may or may not be 0-terminated. It is the responsibility of the caller
to make sure that the :c:type:`wchar_t` string is 0-terminated in case this is
required by the application.
.. c:function:: wchar_t* PyUnicode_AsWideCharString(PyObject *unicode, Py_ssize_t *size)
Convert the Unicode object to a wide character string. The output string
always ends with a nul character. If *size* is not *NULL*, write the number
of wide characters (excluding the trailing 0-termination character) into
*\*size*.
Returns a buffer allocated by :c:func:`PyMem_Alloc` (use :c:func:`PyMem_Free`
to free it) on success. On error, returns *NULL*, *\*size* is undefined and
raises a :exc:`MemoryError`.
.. versionadded:: 3.2
UCS4 Support
""""""""""""
.. versionadded:: 3.3
.. XXX are these meant to be public?
.. c:function:: size_t Py_UCS4_strlen(const Py_UCS4 *u)
Py_UCS4* Py_UCS4_strcpy(Py_UCS4 *s1, const Py_UCS4 *s2)
Py_UCS4* Py_UCS4_strncpy(Py_UCS4 *s1, const Py_UCS4 *s2, size_t n)
Py_UCS4* Py_UCS4_strcat(Py_UCS4 *s1, const Py_UCS4 *s2)
int Py_UCS4_strcmp(const Py_UCS4 *s1, const Py_UCS4 *s2)
int Py_UCS4_strncmp(const Py_UCS4 *s1, const Py_UCS4 *s2, size_t n)
Py_UCS4* Py_UCS4_strchr(const Py_UCS4 *s, Py_UCS4 c)
Py_UCS4* Py_UCS4_strrchr(const Py_UCS4 *s, Py_UCS4 c)
These utility functions work on strings of :c:type:`Py_UCS4` characters and
otherwise behave like the C standard library functions with the same name.
.. _builtincodecs:
Built-in Codecs
^^^^^^^^^^^^^^^
Python provides a set of built-in codecs which are written in C for speed. All of
these codecs are directly usable via the following functions.
Many of the following APIs take two arguments encoding and errors, and they
have the same semantics as the ones of the built-in :func:`str` string object
constructor.
Setting encoding to *NULL* causes the default encoding to be used
which is ASCII. The file system calls should use
:c:func:`PyUnicode_FSConverter` for encoding file names. This uses the
variable :c:data:`Py_FileSystemDefaultEncoding` internally. This
variable should be treated as read-only: on some systems, it will be a
pointer to a static string, on others, it will change at run-time
(such as when the application invokes setlocale).
Error handling is set by errors which may also be set to *NULL* meaning to use
the default handling defined for the codec. Default error handling for all
built-in codecs is "strict" (:exc:`ValueError` is raised).
The codecs all use a similar interface. Only deviation from the following
generic ones are documented for simplicity.
Generic Codecs
""""""""""""""
These are the generic codec APIs:
.. c:function:: PyObject* PyUnicode_Decode(const char *s, Py_ssize_t size, \
const char *encoding, const char *errors)
Create a Unicode object by decoding *size* bytes of the encoded string *s*.
*encoding* and *errors* have the same meaning as the parameters of the same name
in the :func:`unicode` built-in function. The codec to be used is looked up
using the Python codec registry. Return *NULL* if an exception was raised by
the codec.
.. c:function:: PyObject* PyUnicode_AsEncodedString(PyObject *unicode, \
const char *encoding, const char *errors)
Encode a Unicode object and return the result as Python bytes object.
*encoding* and *errors* have the same meaning as the parameters of the same
name in the Unicode :meth:`encode` method. The codec to be used is looked up
using the Python codec registry. Return *NULL* if an exception was raised by
the codec.
.. c:function:: PyObject* PyUnicode_Encode(const Py_UNICODE *s, Py_ssize_t size, \
const char *encoding, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer *s* of the given *size* and return a Python
bytes object. *encoding* and *errors* have the same meaning as the
parameters of the same name in the Unicode :meth:`encode` method. The codec
to be used is looked up using the Python codec registry. Return *NULL* if an
exception was raised by the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsEncodedString`.
UTF-8 Codecs
""""""""""""
These are the UTF-8 codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeUTF8(const char *s, Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the UTF-8 encoded string
*s*. Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_DecodeUTF8Stateful(const char *s, Py_ssize_t size, \
const char *errors, Py_ssize_t *consumed)
If *consumed* is *NULL*, behave like :c:func:`PyUnicode_DecodeUTF8`. If
*consumed* is not *NULL*, trailing incomplete UTF-8 byte sequences will not be
treated as an error. Those bytes will not be decoded and the number of bytes
that have been decoded will be stored in *consumed*.
.. c:function:: PyObject* PyUnicode_AsUTF8String(PyObject *unicode)
Encode a Unicode object using UTF-8 and return the result as Python bytes
object. Error handling is "strict". Return *NULL* if an exception was
raised by the codec.
.. c:function:: char* PyUnicode_AsUTF8AndSize(PyObject *unicode, Py_ssize_t *size)
Return a pointer to the default encoding (UTF-8) of the Unicode object, and
store the size of the encoded representation (in bytes) in *size*. *size*
can be *NULL*, in this case no size will be stored.
In the case of an error, *NULL* is returned with an exception set and no
*size* is stored.
This caches the UTF-8 representation of the string in the Unicode object, and
subsequent calls will return a pointer to the same buffer. The caller is not
responsible for deallocating the buffer.
.. versionadded:: 3.3
.. c:function:: char* PyUnicode_AsUTF8(PyObject *unicode)
As :c:func:`PyUnicode_AsUTF8AndSize`, but does not store the size.
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_EncodeUTF8(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer *s* of the given *size* using UTF-8 and
return a Python bytes object. Return *NULL* if an exception was raised by
the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsUTF8String` or :c:func:`PyUnicode_AsUTF8AndSize`.
UTF-32 Codecs
"""""""""""""
These are the UTF-32 codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeUTF32(const char *s, Py_ssize_t size, \
const char *errors, int *byteorder)
Decode *size* bytes from a UTF-32 encoded buffer string and return the
corresponding Unicode object. *errors* (if non-*NULL*) defines the error
handling. It defaults to "strict".
If *byteorder* is non-*NULL*, the decoder starts decoding using the given byte
order::
*byteorder == -1: little endian
*byteorder == 0: native order
*byteorder == 1: big endian
If ``*byteorder`` is zero, and the first four bytes of the input data are a
byte order mark (BOM), the decoder switches to this byte order and the BOM is
not copied into the resulting Unicode string. If ``*byteorder`` is ``-1`` or
``1``, any byte order mark is copied to the output.
After completion, *\*byteorder* is set to the current byte order at the end
of input data.
In a narrow build codepoints outside the BMP will be decoded as surrogate pairs.
If *byteorder* is *NULL*, the codec starts in native order mode.
Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_DecodeUTF32Stateful(const char *s, Py_ssize_t size, \
const char *errors, int *byteorder, Py_ssize_t *consumed)
If *consumed* is *NULL*, behave like :c:func:`PyUnicode_DecodeUTF32`. If
*consumed* is not *NULL*, :c:func:`PyUnicode_DecodeUTF32Stateful` will not treat
trailing incomplete UTF-32 byte sequences (such as a number of bytes not divisible
by four) as an error. Those bytes will not be decoded and the number of bytes
that have been decoded will be stored in *consumed*.
.. c:function:: PyObject* PyUnicode_AsUTF32String(PyObject *unicode)
Return a Python byte string using the UTF-32 encoding in native byte
order. The string always starts with a BOM mark. Error handling is "strict".
Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeUTF32(const Py_UNICODE *s, Py_ssize_t size, \
const char *errors, int byteorder)
Return a Python bytes object holding the UTF-32 encoded value of the Unicode
data in *s*. Output is written according to the following byte order::
byteorder == -1: little endian
byteorder == 0: native byte order (writes a BOM mark)
byteorder == 1: big endian
If byteorder is ``0``, the output string will always start with the Unicode BOM
mark (U+FEFF). In the other two modes, no BOM mark is prepended.
If *Py_UNICODE_WIDE* is not defined, surrogate pairs will be output
as a single codepoint.
Return *NULL* if an exception was raised by the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsUTF32String`.
UTF-16 Codecs
"""""""""""""
These are the UTF-16 codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeUTF16(const char *s, Py_ssize_t size, \
const char *errors, int *byteorder)
Decode *size* bytes from a UTF-16 encoded buffer string and return the
corresponding Unicode object. *errors* (if non-*NULL*) defines the error
handling. It defaults to "strict".
If *byteorder* is non-*NULL*, the decoder starts decoding using the given byte
order::
*byteorder == -1: little endian
*byteorder == 0: native order
*byteorder == 1: big endian
If ``*byteorder`` is zero, and the first two bytes of the input data are a
byte order mark (BOM), the decoder switches to this byte order and the BOM is
not copied into the resulting Unicode string. If ``*byteorder`` is ``-1`` or
``1``, any byte order mark is copied to the output (where it will result in
either a ``\ufeff`` or a ``\ufffe`` character).
After completion, *\*byteorder* is set to the current byte order at the end
of input data.
If *byteorder* is *NULL*, the codec starts in native order mode.
Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_DecodeUTF16Stateful(const char *s, Py_ssize_t size, \
const char *errors, int *byteorder, Py_ssize_t *consumed)
If *consumed* is *NULL*, behave like :c:func:`PyUnicode_DecodeUTF16`. If
*consumed* is not *NULL*, :c:func:`PyUnicode_DecodeUTF16Stateful` will not treat
trailing incomplete UTF-16 byte sequences (such as an odd number of bytes or a
split surrogate pair) as an error. Those bytes will not be decoded and the
number of bytes that have been decoded will be stored in *consumed*.
.. c:function:: PyObject* PyUnicode_AsUTF16String(PyObject *unicode)
Return a Python byte string using the UTF-16 encoding in native byte
order. The string always starts with a BOM mark. Error handling is "strict".
Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeUTF16(const Py_UNICODE *s, Py_ssize_t size, \
const char *errors, int byteorder)
Return a Python bytes object holding the UTF-16 encoded value of the Unicode
data in *s*. Output is written according to the following byte order::
byteorder == -1: little endian
byteorder == 0: native byte order (writes a BOM mark)
byteorder == 1: big endian
If byteorder is ``0``, the output string will always start with the Unicode BOM
mark (U+FEFF). In the other two modes, no BOM mark is prepended.
If *Py_UNICODE_WIDE* is defined, a single :c:type:`Py_UNICODE` value may get
represented as a surrogate pair. If it is not defined, each :c:type:`Py_UNICODE`
values is interpreted as an UCS-2 character.
Return *NULL* if an exception was raised by the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsUTF16String`.
UTF-7 Codecs
""""""""""""
These are the UTF-7 codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeUTF7(const char *s, Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the UTF-7 encoded string
*s*. Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_DecodeUTF7Stateful(const char *s, Py_ssize_t size, \
const char *errors, Py_ssize_t *consumed)
If *consumed* is *NULL*, behave like :c:func:`PyUnicode_DecodeUTF7`. If
*consumed* is not *NULL*, trailing incomplete UTF-7 base-64 sections will not
be treated as an error. Those bytes will not be decoded and the number of
bytes that have been decoded will be stored in *consumed*.
.. c:function:: PyObject* PyUnicode_EncodeUTF7(const Py_UNICODE *s, Py_ssize_t size, \
int base64SetO, int base64WhiteSpace, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer of the given size using UTF-7 and
return a Python bytes object. Return *NULL* if an exception was raised by
the codec.
If *base64SetO* is nonzero, "Set O" (punctuation that has no otherwise
special meaning) will be encoded in base-64. If *base64WhiteSpace* is
nonzero, whitespace will be encoded in base-64. Both are set to zero for the
Python "utf-7" codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API.
.. XXX replace with what?
Unicode-Escape Codecs
"""""""""""""""""""""
These are the "Unicode Escape" codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeUnicodeEscape(const char *s, \
Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the Unicode-Escape encoded
string *s*. Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_AsUnicodeEscapeString(PyObject *unicode)
Encode a Unicode object using Unicode-Escape and return the result as Python
string object. Error handling is "strict". Return *NULL* if an exception was
raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeUnicodeEscape(const Py_UNICODE *s, Py_ssize_t size)
Encode the :c:type:`Py_UNICODE` buffer of the given *size* using Unicode-Escape and
return a Python string object. Return *NULL* if an exception was raised by the
codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsUnicodeEscapeString`.
Raw-Unicode-Escape Codecs
"""""""""""""""""""""""""
These are the "Raw Unicode Escape" codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeRawUnicodeEscape(const char *s, \
Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the Raw-Unicode-Escape
encoded string *s*. Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_AsRawUnicodeEscapeString(PyObject *unicode)
Encode a Unicode object using Raw-Unicode-Escape and return the result as
Python string object. Error handling is "strict". Return *NULL* if an exception
was raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeRawUnicodeEscape(const Py_UNICODE *s, \
Py_ssize_t size, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer of the given *size* using Raw-Unicode-Escape
and return a Python string object. Return *NULL* if an exception was raised by
the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsRawUnicodeEscapeString`.
Latin-1 Codecs
""""""""""""""
These are the Latin-1 codec APIs: Latin-1 corresponds to the first 256 Unicode
ordinals and only these are accepted by the codecs during encoding.
.. c:function:: PyObject* PyUnicode_DecodeLatin1(const char *s, Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the Latin-1 encoded string
*s*. Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_AsLatin1String(PyObject *unicode)
Encode a Unicode object using Latin-1 and return the result as Python bytes
object. Error handling is "strict". Return *NULL* if an exception was
raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeLatin1(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer of the given *size* using Latin-1 and
return a Python bytes object. Return *NULL* if an exception was raised by
the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsLatin1String`.
ASCII Codecs
""""""""""""
These are the ASCII codec APIs. Only 7-bit ASCII data is accepted. All other
codes generate errors.
.. c:function:: PyObject* PyUnicode_DecodeASCII(const char *s, Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the ASCII encoded string
*s*. Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_AsASCIIString(PyObject *unicode)
Encode a Unicode object using ASCII and return the result as Python bytes
object. Error handling is "strict". Return *NULL* if an exception was
raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeASCII(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer of the given *size* using ASCII and
return a Python bytes object. Return *NULL* if an exception was raised by
the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsASCIIString`.
Character Map Codecs
""""""""""""""""""""
This codec is special in that it can be used to implement many different codecs
(and this is in fact what was done to obtain most of the standard codecs
included in the :mod:`encodings` package). The codec uses mapping to encode and
decode characters.
Decoding mappings must map single string characters to single Unicode
characters, integers (which are then interpreted as Unicode ordinals) or None
(meaning "undefined mapping" and causing an error).
Encoding mappings must map single Unicode characters to single string
characters, integers (which are then interpreted as Latin-1 ordinals) or None
(meaning "undefined mapping" and causing an error).
The mapping objects provided must only support the __getitem__ mapping
interface.
If a character lookup fails with a LookupError, the character is copied as-is
meaning that its ordinal value will be interpreted as Unicode or Latin-1 ordinal
resp. Because of this, mappings only need to contain those mappings which map
characters to different code points.
These are the mapping codec APIs:
.. c:function:: PyObject* PyUnicode_DecodeCharmap(const char *s, Py_ssize_t size, \
PyObject *mapping, const char *errors)
Create a Unicode object by decoding *size* bytes of the encoded string *s* using
the given *mapping* object. Return *NULL* if an exception was raised by the
codec. If *mapping* is *NULL* latin-1 decoding will be done. Else it can be a
dictionary mapping byte or a unicode string, which is treated as a lookup table.
Byte values greater that the length of the string and U+FFFE "characters" are
treated as "undefined mapping".
.. c:function:: PyObject* PyUnicode_AsCharmapString(PyObject *unicode, PyObject *mapping)
Encode a Unicode object using the given *mapping* object and return the result
as Python string object. Error handling is "strict". Return *NULL* if an
exception was raised by the codec.
The following codec API is special in that maps Unicode to Unicode.
.. c:function:: PyObject* PyUnicode_TranslateCharmap(const Py_UNICODE *s, Py_ssize_t size, \
PyObject *table, const char *errors)
Translate a :c:type:`Py_UNICODE` buffer of the given *size* by applying a
character mapping *table* to it and return the resulting Unicode object. Return
*NULL* when an exception was raised by the codec.
The *mapping* table must map Unicode ordinal integers to Unicode ordinal
integers or None (causing deletion of the character).
Mapping tables need only provide the :meth:`__getitem__` interface; dictionaries
and sequences work well. Unmapped character ordinals (ones which cause a
:exc:`LookupError`) are left untouched and are copied as-is.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API.
.. XXX replace with what?
.. c:function:: PyObject* PyUnicode_EncodeCharmap(const Py_UNICODE *s, Py_ssize_t size, \
PyObject *mapping, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer of the given *size* using the given
*mapping* object and return a Python string object. Return *NULL* if an
exception was raised by the codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsCharmapString`.
MBCS codecs for Windows
"""""""""""""""""""""""
These are the MBCS codec APIs. They are currently only available on Windows and
use the Win32 MBCS converters to implement the conversions. Note that MBCS (or
DBCS) is a class of encodings, not just one. The target encoding is defined by
the user settings on the machine running the codec.
.. c:function:: PyObject* PyUnicode_DecodeMBCS(const char *s, Py_ssize_t size, const char *errors)
Create a Unicode object by decoding *size* bytes of the MBCS encoded string *s*.
Return *NULL* if an exception was raised by the codec.
.. c:function:: PyObject* PyUnicode_DecodeMBCSStateful(const char *s, int size, \
const char *errors, int *consumed)
If *consumed* is *NULL*, behave like :c:func:`PyUnicode_DecodeMBCS`. If
*consumed* is not *NULL*, :c:func:`PyUnicode_DecodeMBCSStateful` will not decode
trailing lead byte and the number of bytes that have been decoded will be stored
in *consumed*.
.. c:function:: PyObject* PyUnicode_AsMBCSString(PyObject *unicode)
Encode a Unicode object using MBCS and return the result as Python bytes
object. Error handling is "strict". Return *NULL* if an exception was
raised by the codec.
.. c:function:: PyObject* PyUnicode_EncodeCodePage(int code_page, PyObject *unicode, const char *errors)
Encode the Unicode object using the specified code page and return a Python
bytes object. Return *NULL* if an exception was raised by the codec. Use
:c:data:`CP_ACP` code page to get the MBCS encoder.
.. versionadded:: 3.3
.. c:function:: PyObject* PyUnicode_EncodeMBCS(const Py_UNICODE *s, Py_ssize_t size, const char *errors)
Encode the :c:type:`Py_UNICODE` buffer of the given *size* using MBCS and return
a Python bytes object. Return *NULL* if an exception was raised by the
codec.
.. deprecated-removed:: 3.3 4.0
Part of the old-style :c:type:`Py_UNICODE` API; please migrate to using
:c:func:`PyUnicode_AsMBCSString` or :c:func:`PyUnicode_EncodeCodePage`.
Methods & Slots
"""""""""""""""
.. _unicodemethodsandslots:
Methods and Slot Functions
^^^^^^^^^^^^^^^^^^^^^^^^^^
The following APIs are capable of handling Unicode objects and strings on input
(we refer to them as strings in the descriptions) and return Unicode objects or
integers as appropriate.
They all return *NULL* or ``-1`` if an exception occurs.
.. c:function:: PyObject* PyUnicode_Concat(PyObject *left, PyObject *right)
Concat two strings giving a new Unicode string.
.. c:function:: PyObject* PyUnicode_Split(PyObject *s, PyObject *sep, Py_ssize_t maxsplit)
Split a string giving a list of Unicode strings. If *sep* is *NULL*, splitting
will be done at all whitespace substrings. Otherwise, splits occur at the given
separator. At most *maxsplit* splits will be done. If negative, no limit is
set. Separators are not included in the resulting list.
.. c:function:: PyObject* PyUnicode_Splitlines(PyObject *s, int keepend)
Split a Unicode string at line breaks, returning a list of Unicode strings.
CRLF is considered to be one line break. If *keepend* is 0, the Line break
characters are not included in the resulting strings.
.. c:function:: PyObject* PyUnicode_Translate(PyObject *str, PyObject *table, \
const char *errors)
Translate a string by applying a character mapping table to it and return the
resulting Unicode object.
The mapping table must map Unicode ordinal integers to Unicode ordinal integers
or None (causing deletion of the character).
Mapping tables need only provide the :meth:`__getitem__` interface; dictionaries
and sequences work well. Unmapped character ordinals (ones which cause a
:exc:`LookupError`) are left untouched and are copied as-is.
*errors* has the usual meaning for codecs. It may be *NULL* which indicates to
use the default error handling.
.. c:function:: PyObject* PyUnicode_Join(PyObject *separator, PyObject *seq)
Join a sequence of strings using the given *separator* and return the resulting
Unicode string.
.. c:function:: int PyUnicode_Tailmatch(PyObject *str, PyObject *substr, \
Py_ssize_t start, Py_ssize_t end, int direction)
Return 1 if *substr* matches ``str[start:end]`` at the given tail end
(*direction* == -1 means to do a prefix match, *direction* == 1 a suffix match),
0 otherwise. Return ``-1`` if an error occurred.
.. c:function:: Py_ssize_t PyUnicode_Find(PyObject *str, PyObject *substr, \
Py_ssize_t start, Py_ssize_t end, int direction)
Return the first position of *substr* in ``str[start:end]`` using the given
*direction* (*direction* == 1 means to do a forward search, *direction* == -1 a
backward search). The return value is the index of the first match; a value of
``-1`` indicates that no match was found, and ``-2`` indicates that an error
occurred and an exception has been set.
.. c:function:: Py_ssize_t PyUnicode_FindChar(PyObject *str, Py_UCS4 ch, \
Py_ssize_t start, Py_ssize_t end, int direction)
Return the first position of the character *ch* in ``str[start:end]`` using
the given *direction* (*direction* == 1 means to do a forward search,
*direction* == -1 a backward search). The return value is the index of the
first match; a value of ``-1`` indicates that no match was found, and ``-2``
indicates that an error occurred and an exception has been set.
.. versionadded:: 3.3
.. c:function:: Py_ssize_t PyUnicode_Count(PyObject *str, PyObject *substr, \
Py_ssize_t start, Py_ssize_t end)
Return the number of non-overlapping occurrences of *substr* in
``str[start:end]``. Return ``-1`` if an error occurred.
.. c:function:: PyObject* PyUnicode_Replace(PyObject *str, PyObject *substr, \
PyObject *replstr, Py_ssize_t maxcount)
Replace at most *maxcount* occurrences of *substr* in *str* with *replstr* and
return the resulting Unicode object. *maxcount* == -1 means replace all
occurrences.
.. c:function:: int PyUnicode_Compare(PyObject *left, PyObject *right)
Compare two strings and return -1, 0, 1 for less than, equal, and greater than,
respectively.
.. c:function:: int PyUnicode_CompareWithASCIIString(PyObject *uni, char *string)
Compare a unicode object, *uni*, with *string* and return -1, 0, 1 for less
than, equal, and greater than, respectively. It is best to pass only
ASCII-encoded strings, but the function interprets the input string as
ISO-8859-1 if it contains non-ASCII characters".
.. c:function:: int PyUnicode_RichCompare(PyObject *left, PyObject *right, int op)
Rich compare two unicode strings and return one of the following:
* ``NULL`` in case an exception was raised
* :const:`Py_True` or :const:`Py_False` for successful comparisons
* :const:`Py_NotImplemented` in case the type combination is unknown
Note that :const:`Py_EQ` and :const:`Py_NE` comparisons can cause a
:exc:`UnicodeWarning` in case the conversion of the arguments to Unicode fails
with a :exc:`UnicodeDecodeError`.
Possible values for *op* are :const:`Py_GT`, :const:`Py_GE`, :const:`Py_EQ`,
:const:`Py_NE`, :const:`Py_LT`, and :const:`Py_LE`.
.. c:function:: PyObject* PyUnicode_Format(PyObject *format, PyObject *args)
Return a new string object from *format* and *args*; this is analogous to
``format % args``. The *args* argument must be a tuple.
.. c:function:: int PyUnicode_Contains(PyObject *container, PyObject *element)
Check whether *element* is contained in *container* and return true or false
accordingly.
*element* has to coerce to a one element Unicode string. ``-1`` is returned
if there was an error.
.. c:function:: void PyUnicode_InternInPlace(PyObject **string)
Intern the argument *\*string* in place. The argument must be the address of a
pointer variable pointing to a Python unicode string object. If there is an
existing interned string that is the same as *\*string*, it sets *\*string* to
it (decrementing the reference count of the old string object and incrementing
the reference count of the interned string object), otherwise it leaves
*\*string* alone and interns it (incrementing its reference count).
(Clarification: even though there is a lot of talk about reference counts, think
of this function as reference-count-neutral; you own the object after the call
if and only if you owned it before the call.)
.. c:function:: PyObject* PyUnicode_InternFromString(const char *v)
A combination of :c:func:`PyUnicode_FromString` and
:c:func:`PyUnicode_InternInPlace`, returning either a new unicode string
object that has been interned, or a new ("owned") reference to an earlier
interned string object with the same value.
|