1:mod:`xml.parsers.expat` --- Fast XML parsing using Expat 2========================================================= 3 4.. module:: xml.parsers.expat 5 :synopsis: An interface to the Expat non-validating XML parser. 6 7.. moduleauthor:: Paul Prescod <paul@prescod.net> 8 9-------------- 10 11.. Markup notes: 12 13 Many of the attributes of the XMLParser objects are callbacks. Since 14 signature information must be presented, these are described using the method 15 directive. Since they are attributes which are set by client code, in-text 16 references to these attributes should be marked using the :member: role. 17 18 19.. warning:: 20 21 The :mod:`pyexpat` module is not secure against maliciously 22 constructed data. If you need to parse untrusted or unauthenticated data see 23 :ref:`xml-vulnerabilities`. 24 25 26.. index:: single: Expat 27 28The :mod:`xml.parsers.expat` module is a Python interface to the Expat 29non-validating XML parser. The module provides a single extension type, 30:class:`xmlparser`, that represents the current state of an XML parser. After 31an :class:`xmlparser` object has been created, various attributes of the object 32can be set to handler functions. When an XML document is then fed to the 33parser, the handler functions are called for the character data and markup in 34the XML document. 35 36.. index:: module: pyexpat 37 38This module uses the :mod:`pyexpat` module to provide access to the Expat 39parser. Direct use of the :mod:`pyexpat` module is deprecated. 40 41This module provides one exception and one type object: 42 43 44.. exception:: ExpatError 45 46 The exception raised when Expat reports an error. See section 47 :ref:`expaterror-objects` for more information on interpreting Expat errors. 48 49 50.. exception:: error 51 52 Alias for :exc:`ExpatError`. 53 54 55.. data:: XMLParserType 56 57 The type of the return values from the :func:`ParserCreate` function. 58 59The :mod:`xml.parsers.expat` module contains two functions: 60 61 62.. function:: ErrorString(errno) 63 64 Returns an explanatory string for a given error number *errno*. 65 66 67.. function:: ParserCreate(encoding=None, namespace_separator=None) 68 69 Creates and returns a new :class:`xmlparser` object. *encoding*, if specified, 70 must be a string naming the encoding used by the XML data. Expat doesn't 71 support as many encodings as Python does, and its repertoire of encodings can't 72 be extended; it supports UTF-8, UTF-16, ISO-8859-1 (Latin1), and ASCII. If 73 *encoding* [1]_ is given it will override the implicit or explicit encoding of the 74 document. 75 76 Expat can optionally do XML namespace processing for you, enabled by providing a 77 value for *namespace_separator*. The value must be a one-character string; a 78 :exc:`ValueError` will be raised if the string has an illegal length (``None`` 79 is considered the same as omission). When namespace processing is enabled, 80 element type names and attribute names that belong to a namespace will be 81 expanded. The element name passed to the element handlers 82 :attr:`StartElementHandler` and :attr:`EndElementHandler` will be the 83 concatenation of the namespace URI, the namespace separator character, and the 84 local part of the name. If the namespace separator is a zero byte (``chr(0)``) 85 then the namespace URI and the local part will be concatenated without any 86 separator. 87 88 For example, if *namespace_separator* is set to a space character (``' '``) and 89 the following document is parsed: 90 91 .. code-block:: xml 92 93 <?xml version="1.0"?> 94 <root xmlns = "http://default-namespace.org/" 95 xmlns:py = "http://www.python.org/ns/"> 96 <py:elem1 /> 97 <elem2 xmlns="" /> 98 </root> 99 100 :attr:`StartElementHandler` will receive the following strings for each 101 element:: 102 103 http://default-namespace.org/ root 104 http://www.python.org/ns/ elem1 105 elem2 106 107 Due to limitations in the ``Expat`` library used by :mod:`pyexpat`, 108 the :class:`xmlparser` instance returned can only be used to parse a single 109 XML document. Call ``ParserCreate`` for each document to provide unique 110 parser instances. 111 112 113.. seealso:: 114 115 `The Expat XML Parser <http://www.libexpat.org/>`_ 116 Home page of the Expat project. 117 118 119.. _xmlparser-objects: 120 121XMLParser Objects 122----------------- 123 124:class:`xmlparser` objects have the following methods: 125 126 127.. method:: xmlparser.Parse(data[, isfinal]) 128 129 Parses the contents of the string *data*, calling the appropriate handler 130 functions to process the parsed data. *isfinal* must be true on the final call 131 to this method; it allows the parsing of a single file in fragments, 132 not the submission of multiple files. 133 *data* can be the empty string at any time. 134 135 136.. method:: xmlparser.ParseFile(file) 137 138 Parse XML data reading from the object *file*. *file* only needs to provide 139 the ``read(nbytes)`` method, returning the empty string when there's no more 140 data. 141 142 143.. method:: xmlparser.SetBase(base) 144 145 Sets the base to be used for resolving relative URIs in system identifiers in 146 declarations. Resolving relative identifiers is left to the application: this 147 value will be passed through as the *base* argument to the 148 :func:`ExternalEntityRefHandler`, :func:`NotationDeclHandler`, and 149 :func:`UnparsedEntityDeclHandler` functions. 150 151 152.. method:: xmlparser.GetBase() 153 154 Returns a string containing the base set by a previous call to :meth:`SetBase`, 155 or ``None`` if :meth:`SetBase` hasn't been called. 156 157 158.. method:: xmlparser.GetInputContext() 159 160 Returns the input data that generated the current event as a string. The data is 161 in the encoding of the entity which contains the text. When called while an 162 event handler is not active, the return value is ``None``. 163 164 165.. method:: xmlparser.ExternalEntityParserCreate(context[, encoding]) 166 167 Create a "child" parser which can be used to parse an external parsed entity 168 referred to by content parsed by the parent parser. The *context* parameter 169 should be the string passed to the :meth:`ExternalEntityRefHandler` handler 170 function, described below. The child parser is created with the 171 :attr:`ordered_attributes` and :attr:`specified_attributes` set to the values of 172 this parser. 173 174.. method:: xmlparser.SetParamEntityParsing(flag) 175 176 Control parsing of parameter entities (including the external DTD subset). 177 Possible *flag* values are :const:`XML_PARAM_ENTITY_PARSING_NEVER`, 178 :const:`XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE` and 179 :const:`XML_PARAM_ENTITY_PARSING_ALWAYS`. Return true if setting the flag 180 was successful. 181 182.. method:: xmlparser.UseForeignDTD([flag]) 183 184 Calling this with a true value for *flag* (the default) will cause Expat to call 185 the :attr:`ExternalEntityRefHandler` with :const:`None` for all arguments to 186 allow an alternate DTD to be loaded. If the document does not contain a 187 document type declaration, the :attr:`ExternalEntityRefHandler` will still be 188 called, but the :attr:`StartDoctypeDeclHandler` and 189 :attr:`EndDoctypeDeclHandler` will not be called. 190 191 Passing a false value for *flag* will cancel a previous call that passed a true 192 value, but otherwise has no effect. 193 194 This method can only be called before the :meth:`Parse` or :meth:`ParseFile` 195 methods are called; calling it after either of those have been called causes 196 :exc:`ExpatError` to be raised with the :attr:`code` attribute set to 197 ``errors.codes[errors.XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING]``. 198 199:class:`xmlparser` objects have the following attributes: 200 201 202.. attribute:: xmlparser.buffer_size 203 204 The size of the buffer used when :attr:`buffer_text` is true. 205 A new buffer size can be set by assigning a new integer value 206 to this attribute. 207 When the size is changed, the buffer will be flushed. 208 209 210.. attribute:: xmlparser.buffer_text 211 212 Setting this to true causes the :class:`xmlparser` object to buffer textual 213 content returned by Expat to avoid multiple calls to the 214 :meth:`CharacterDataHandler` callback whenever possible. This can improve 215 performance substantially since Expat normally breaks character data into chunks 216 at every line ending. This attribute is false by default, and may be changed at 217 any time. 218 219 220.. attribute:: xmlparser.buffer_used 221 222 If :attr:`buffer_text` is enabled, the number of bytes stored in the buffer. 223 These bytes represent UTF-8 encoded text. This attribute has no meaningful 224 interpretation when :attr:`buffer_text` is false. 225 226 227.. attribute:: xmlparser.ordered_attributes 228 229 Setting this attribute to a non-zero integer causes the attributes to be 230 reported as a list rather than a dictionary. The attributes are presented in 231 the order found in the document text. For each attribute, two list entries are 232 presented: the attribute name and the attribute value. (Older versions of this 233 module also used this format.) By default, this attribute is false; it may be 234 changed at any time. 235 236 237.. attribute:: xmlparser.specified_attributes 238 239 If set to a non-zero integer, the parser will report only those attributes which 240 were specified in the document instance and not those which were derived from 241 attribute declarations. Applications which set this need to be especially 242 careful to use what additional information is available from the declarations as 243 needed to comply with the standards for the behavior of XML processors. By 244 default, this attribute is false; it may be changed at any time. 245 246 247The following attributes contain values relating to the most recent error 248encountered by an :class:`xmlparser` object, and will only have correct values 249once a call to :meth:`Parse` or :meth:`ParseFile` has raised an 250:exc:`xml.parsers.expat.ExpatError` exception. 251 252 253.. attribute:: xmlparser.ErrorByteIndex 254 255 Byte index at which an error occurred. 256 257 258.. attribute:: xmlparser.ErrorCode 259 260 Numeric code specifying the problem. This value can be passed to the 261 :func:`ErrorString` function, or compared to one of the constants defined in the 262 ``errors`` object. 263 264 265.. attribute:: xmlparser.ErrorColumnNumber 266 267 Column number at which an error occurred. 268 269 270.. attribute:: xmlparser.ErrorLineNumber 271 272 Line number at which an error occurred. 273 274The following attributes contain values relating to the current parse location 275in an :class:`xmlparser` object. During a callback reporting a parse event they 276indicate the location of the first of the sequence of characters that generated 277the event. When called outside of a callback, the position indicated will be 278just past the last parse event (regardless of whether there was an associated 279callback). 280 281 282.. attribute:: xmlparser.CurrentByteIndex 283 284 Current byte index in the parser input. 285 286 287.. attribute:: xmlparser.CurrentColumnNumber 288 289 Current column number in the parser input. 290 291 292.. attribute:: xmlparser.CurrentLineNumber 293 294 Current line number in the parser input. 295 296Here is the list of handlers that can be set. To set a handler on an 297:class:`xmlparser` object *o*, use ``o.handlername = func``. *handlername* must 298be taken from the following list, and *func* must be a callable object accepting 299the correct number of arguments. The arguments are all strings, unless 300otherwise stated. 301 302 303.. method:: xmlparser.XmlDeclHandler(version, encoding, standalone) 304 305 Called when the XML declaration is parsed. The XML declaration is the 306 (optional) declaration of the applicable version of the XML recommendation, the 307 encoding of the document text, and an optional "standalone" declaration. 308 *version* and *encoding* will be strings, and *standalone* will be ``1`` if the 309 document is declared standalone, ``0`` if it is declared not to be standalone, 310 or ``-1`` if the standalone clause was omitted. This is only available with 311 Expat version 1.95.0 or newer. 312 313 314.. method:: xmlparser.StartDoctypeDeclHandler(doctypeName, systemId, publicId, has_internal_subset) 315 316 Called when Expat begins parsing the document type declaration (``<!DOCTYPE 317 ...``). The *doctypeName* is provided exactly as presented. The *systemId* and 318 *publicId* parameters give the system and public identifiers if specified, or 319 ``None`` if omitted. *has_internal_subset* will be true if the document 320 contains and internal document declaration subset. This requires Expat version 321 1.2 or newer. 322 323 324.. method:: xmlparser.EndDoctypeDeclHandler() 325 326 Called when Expat is done parsing the document type declaration. This requires 327 Expat version 1.2 or newer. 328 329 330.. method:: xmlparser.ElementDeclHandler(name, model) 331 332 Called once for each element type declaration. *name* is the name of the 333 element type, and *model* is a representation of the content model. 334 335 336.. method:: xmlparser.AttlistDeclHandler(elname, attname, type, default, required) 337 338 Called for each declared attribute for an element type. If an attribute list 339 declaration declares three attributes, this handler is called three times, once 340 for each attribute. *elname* is the name of the element to which the 341 declaration applies and *attname* is the name of the attribute declared. The 342 attribute type is a string passed as *type*; the possible values are 343 ``'CDATA'``, ``'ID'``, ``'IDREF'``, ... *default* gives the default value for 344 the attribute used when the attribute is not specified by the document instance, 345 or ``None`` if there is no default value (``#IMPLIED`` values). If the 346 attribute is required to be given in the document instance, *required* will be 347 true. This requires Expat version 1.95.0 or newer. 348 349 350.. method:: xmlparser.StartElementHandler(name, attributes) 351 352 Called for the start of every element. *name* is a string containing the 353 element name, and *attributes* is the element attributes. If 354 :attr:`ordered_attributes` is true, this is a list (see 355 :attr:`ordered_attributes` for a full description). Otherwise it's a 356 dictionary mapping names to values. 357 358 359.. method:: xmlparser.EndElementHandler(name) 360 361 Called for the end of every element. 362 363 364.. method:: xmlparser.ProcessingInstructionHandler(target, data) 365 366 Called for every processing instruction. 367 368 369.. method:: xmlparser.CharacterDataHandler(data) 370 371 Called for character data. This will be called for normal character data, CDATA 372 marked content, and ignorable whitespace. Applications which must distinguish 373 these cases can use the :attr:`StartCdataSectionHandler`, 374 :attr:`EndCdataSectionHandler`, and :attr:`ElementDeclHandler` callbacks to 375 collect the required information. 376 377 378.. method:: xmlparser.UnparsedEntityDeclHandler(entityName, base, systemId, publicId, notationName) 379 380 Called for unparsed (NDATA) entity declarations. This is only present for 381 version 1.2 of the Expat library; for more recent versions, use 382 :attr:`EntityDeclHandler` instead. (The underlying function in the Expat 383 library has been declared obsolete.) 384 385 386.. method:: xmlparser.EntityDeclHandler(entityName, is_parameter_entity, value, base, systemId, publicId, notationName) 387 388 Called for all entity declarations. For parameter and internal entities, 389 *value* will be a string giving the declared contents of the entity; this will 390 be ``None`` for external entities. The *notationName* parameter will be 391 ``None`` for parsed entities, and the name of the notation for unparsed 392 entities. *is_parameter_entity* will be true if the entity is a parameter entity 393 or false for general entities (most applications only need to be concerned with 394 general entities). This is only available starting with version 1.95.0 of the 395 Expat library. 396 397 398.. method:: xmlparser.NotationDeclHandler(notationName, base, systemId, publicId) 399 400 Called for notation declarations. *notationName*, *base*, and *systemId*, and 401 *publicId* are strings if given. If the public identifier is omitted, 402 *publicId* will be ``None``. 403 404 405.. method:: xmlparser.StartNamespaceDeclHandler(prefix, uri) 406 407 Called when an element contains a namespace declaration. Namespace declarations 408 are processed before the :attr:`StartElementHandler` is called for the element 409 on which declarations are placed. 410 411 412.. method:: xmlparser.EndNamespaceDeclHandler(prefix) 413 414 Called when the closing tag is reached for an element that contained a 415 namespace declaration. This is called once for each namespace declaration on 416 the element in the reverse of the order for which the 417 :attr:`StartNamespaceDeclHandler` was called to indicate the start of each 418 namespace declaration's scope. Calls to this handler are made after the 419 corresponding :attr:`EndElementHandler` for the end of the element. 420 421 422.. method:: xmlparser.CommentHandler(data) 423 424 Called for comments. *data* is the text of the comment, excluding the leading 425 ``'<!-``\ ``-'`` and trailing ``'-``\ ``->'``. 426 427 428.. method:: xmlparser.StartCdataSectionHandler() 429 430 Called at the start of a CDATA section. This and :attr:`EndCdataSectionHandler` 431 are needed to be able to identify the syntactical start and end for CDATA 432 sections. 433 434 435.. method:: xmlparser.EndCdataSectionHandler() 436 437 Called at the end of a CDATA section. 438 439 440.. method:: xmlparser.DefaultHandler(data) 441 442 Called for any characters in the XML document for which no applicable handler 443 has been specified. This means characters that are part of a construct which 444 could be reported, but for which no handler has been supplied. 445 446 447.. method:: xmlparser.DefaultHandlerExpand(data) 448 449 This is the same as the :func:`DefaultHandler`, but doesn't inhibit expansion 450 of internal entities. The entity reference will not be passed to the default 451 handler. 452 453 454.. method:: xmlparser.NotStandaloneHandler() 455 456 Called if the XML document hasn't been declared as being a standalone document. 457 This happens when there is an external subset or a reference to a parameter 458 entity, but the XML declaration does not set standalone to ``yes`` in an XML 459 declaration. If this handler returns ``0``, then the parser will raise an 460 :const:`XML_ERROR_NOT_STANDALONE` error. If this handler is not set, no 461 exception is raised by the parser for this condition. 462 463 464.. method:: xmlparser.ExternalEntityRefHandler(context, base, systemId, publicId) 465 466 Called for references to external entities. *base* is the current base, as set 467 by a previous call to :meth:`SetBase`. The public and system identifiers, 468 *systemId* and *publicId*, are strings if given; if the public identifier is not 469 given, *publicId* will be ``None``. The *context* value is opaque and should 470 only be used as described below. 471 472 For external entities to be parsed, this handler must be implemented. It is 473 responsible for creating the sub-parser using 474 ``ExternalEntityParserCreate(context)``, initializing it with the appropriate 475 callbacks, and parsing the entity. This handler should return an integer; if it 476 returns ``0``, the parser will raise an 477 :const:`XML_ERROR_EXTERNAL_ENTITY_HANDLING` error, otherwise parsing will 478 continue. 479 480 If this handler is not provided, external entities are reported by the 481 :attr:`DefaultHandler` callback, if provided. 482 483 484.. _expaterror-objects: 485 486ExpatError Exceptions 487--------------------- 488 489.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org> 490 491 492:exc:`ExpatError` exceptions have a number of interesting attributes: 493 494 495.. attribute:: ExpatError.code 496 497 Expat's internal error number for the specific error. The 498 :data:`errors.messages <xml.parsers.expat.errors.messages>` dictionary maps 499 these error numbers to Expat's error messages. For example:: 500 501 from xml.parsers.expat import ParserCreate, ExpatError, errors 502 503 p = ParserCreate() 504 try: 505 p.Parse(some_xml_document) 506 except ExpatError as err: 507 print("Error:", errors.messages[err.code]) 508 509 The :mod:`~xml.parsers.expat.errors` module also provides error message 510 constants and a dictionary :data:`~xml.parsers.expat.errors.codes` mapping 511 these messages back to the error codes, see below. 512 513 514.. attribute:: ExpatError.lineno 515 516 Line number on which the error was detected. The first line is numbered ``1``. 517 518 519.. attribute:: ExpatError.offset 520 521 Character offset into the line where the error occurred. The first column is 522 numbered ``0``. 523 524 525.. _expat-example: 526 527Example 528------- 529 530The following program defines three handlers that just print out their 531arguments. :: 532 533 import xml.parsers.expat 534 535 # 3 handler functions 536 def start_element(name, attrs): 537 print('Start element:', name, attrs) 538 def end_element(name): 539 print('End element:', name) 540 def char_data(data): 541 print('Character data:', repr(data)) 542 543 p = xml.parsers.expat.ParserCreate() 544 545 p.StartElementHandler = start_element 546 p.EndElementHandler = end_element 547 p.CharacterDataHandler = char_data 548 549 p.Parse("""<?xml version="1.0"?> 550 <parent id="top"><child1 name="paul">Text goes here</child1> 551 <child2 name="fred">More text</child2> 552 </parent>""", 1) 553 554The output from this program is:: 555 556 Start element: parent {'id': 'top'} 557 Start element: child1 {'name': 'paul'} 558 Character data: 'Text goes here' 559 End element: child1 560 Character data: '\n' 561 Start element: child2 {'name': 'fred'} 562 Character data: 'More text' 563 End element: child2 564 Character data: '\n' 565 End element: parent 566 567 568.. _expat-content-models: 569 570Content Model Descriptions 571-------------------------- 572 573.. module:: xml.parsers.expat.model 574 575.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org> 576 577Content models are described using nested tuples. Each tuple contains four 578values: the type, the quantifier, the name, and a tuple of children. Children 579are simply additional content model descriptions. 580 581The values of the first two fields are constants defined in the 582:mod:`xml.parsers.expat.model` module. These constants can be collected in two 583groups: the model type group and the quantifier group. 584 585The constants in the model type group are: 586 587 588.. data:: XML_CTYPE_ANY 589 :noindex: 590 591 The element named by the model name was declared to have a content model of 592 ``ANY``. 593 594 595.. data:: XML_CTYPE_CHOICE 596 :noindex: 597 598 The named element allows a choice from a number of options; this is used for 599 content models such as ``(A | B | C)``. 600 601 602.. data:: XML_CTYPE_EMPTY 603 :noindex: 604 605 Elements which are declared to be ``EMPTY`` have this model type. 606 607 608.. data:: XML_CTYPE_MIXED 609 :noindex: 610 611 612.. data:: XML_CTYPE_NAME 613 :noindex: 614 615 616.. data:: XML_CTYPE_SEQ 617 :noindex: 618 619 Models which represent a series of models which follow one after the other are 620 indicated with this model type. This is used for models such as ``(A, B, C)``. 621 622The constants in the quantifier group are: 623 624 625.. data:: XML_CQUANT_NONE 626 :noindex: 627 628 No modifier is given, so it can appear exactly once, as for ``A``. 629 630 631.. data:: XML_CQUANT_OPT 632 :noindex: 633 634 The model is optional: it can appear once or not at all, as for ``A?``. 635 636 637.. data:: XML_CQUANT_PLUS 638 :noindex: 639 640 The model must occur one or more times (like ``A+``). 641 642 643.. data:: XML_CQUANT_REP 644 :noindex: 645 646 The model must occur zero or more times, as for ``A*``. 647 648 649.. _expat-errors: 650 651Expat error constants 652--------------------- 653 654.. module:: xml.parsers.expat.errors 655 656The following constants are provided in the :mod:`xml.parsers.expat.errors` 657module. These constants are useful in interpreting some of the attributes of 658the :exc:`ExpatError` exception objects raised when an error has occurred. 659Since for backwards compatibility reasons, the constants' value is the error 660*message* and not the numeric error *code*, you do this by comparing its 661:attr:`code` attribute with 662:samp:`errors.codes[errors.XML_ERROR_{CONSTANT_NAME}]`. 663 664The ``errors`` module has the following attributes: 665 666.. data:: codes 667 668 A dictionary mapping numeric error codes to their string descriptions. 669 670 .. versionadded:: 3.2 671 672 673.. data:: messages 674 675 A dictionary mapping string descriptions to their error codes. 676 677 .. versionadded:: 3.2 678 679 680.. data:: XML_ERROR_ASYNC_ENTITY 681 682 683.. data:: XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF 684 685 An entity reference in an attribute value referred to an external entity instead 686 of an internal entity. 687 688 689.. data:: XML_ERROR_BAD_CHAR_REF 690 691 A character reference referred to a character which is illegal in XML (for 692 example, character ``0``, or '``�``'). 693 694 695.. data:: XML_ERROR_BINARY_ENTITY_REF 696 697 An entity reference referred to an entity which was declared with a notation, so 698 cannot be parsed. 699 700 701.. data:: XML_ERROR_DUPLICATE_ATTRIBUTE 702 703 An attribute was used more than once in a start tag. 704 705 706.. data:: XML_ERROR_INCORRECT_ENCODING 707 708 709.. data:: XML_ERROR_INVALID_TOKEN 710 711 Raised when an input byte could not properly be assigned to a character; for 712 example, a NUL byte (value ``0``) in a UTF-8 input stream. 713 714 715.. data:: XML_ERROR_JUNK_AFTER_DOC_ELEMENT 716 717 Something other than whitespace occurred after the document element. 718 719 720.. data:: XML_ERROR_MISPLACED_XML_PI 721 722 An XML declaration was found somewhere other than the start of the input data. 723 724 725.. data:: XML_ERROR_NO_ELEMENTS 726 727 The document contains no elements (XML requires all documents to contain exactly 728 one top-level element).. 729 730 731.. data:: XML_ERROR_NO_MEMORY 732 733 Expat was not able to allocate memory internally. 734 735 736.. data:: XML_ERROR_PARAM_ENTITY_REF 737 738 A parameter entity reference was found where it was not allowed. 739 740 741.. data:: XML_ERROR_PARTIAL_CHAR 742 743 An incomplete character was found in the input. 744 745 746.. data:: XML_ERROR_RECURSIVE_ENTITY_REF 747 748 An entity reference contained another reference to the same entity; possibly via 749 a different name, and possibly indirectly. 750 751 752.. data:: XML_ERROR_SYNTAX 753 754 Some unspecified syntax error was encountered. 755 756 757.. data:: XML_ERROR_TAG_MISMATCH 758 759 An end tag did not match the innermost open start tag. 760 761 762.. data:: XML_ERROR_UNCLOSED_TOKEN 763 764 Some token (such as a start tag) was not closed before the end of the stream or 765 the next token was encountered. 766 767 768.. data:: XML_ERROR_UNDEFINED_ENTITY 769 770 A reference was made to an entity which was not defined. 771 772 773.. data:: XML_ERROR_UNKNOWN_ENCODING 774 775 The document encoding is not supported by Expat. 776 777 778.. data:: XML_ERROR_UNCLOSED_CDATA_SECTION 779 780 A CDATA marked section was not closed. 781 782 783.. data:: XML_ERROR_EXTERNAL_ENTITY_HANDLING 784 785 786.. data:: XML_ERROR_NOT_STANDALONE 787 788 The parser determined that the document was not "standalone" though it declared 789 itself to be in the XML declaration, and the :attr:`NotStandaloneHandler` was 790 set and returned ``0``. 791 792 793.. data:: XML_ERROR_UNEXPECTED_STATE 794 795 796.. data:: XML_ERROR_ENTITY_DECLARED_IN_PE 797 798 799.. data:: XML_ERROR_FEATURE_REQUIRES_XML_DTD 800 801 An operation was requested that requires DTD support to be compiled in, but 802 Expat was configured without DTD support. This should never be reported by a 803 standard build of the :mod:`xml.parsers.expat` module. 804 805 806.. data:: XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING 807 808 A behavioral change was requested after parsing started that can only be changed 809 before parsing has started. This is (currently) only raised by 810 :meth:`UseForeignDTD`. 811 812 813.. data:: XML_ERROR_UNBOUND_PREFIX 814 815 An undeclared prefix was found when namespace processing was enabled. 816 817 818.. data:: XML_ERROR_UNDECLARING_PREFIX 819 820 The document attempted to remove the namespace declaration associated with a 821 prefix. 822 823 824.. data:: XML_ERROR_INCOMPLETE_PE 825 826 A parameter entity contained incomplete markup. 827 828 829.. data:: XML_ERROR_XML_DECL 830 831 The document contained no document element at all. 832 833 834.. data:: XML_ERROR_TEXT_DECL 835 836 There was an error parsing a text declaration in an external entity. 837 838 839.. data:: XML_ERROR_PUBLICID 840 841 Characters were found in the public id that are not allowed. 842 843 844.. data:: XML_ERROR_SUSPENDED 845 846 The requested operation was made on a suspended parser, but isn't allowed. This 847 includes attempts to provide additional input or to stop the parser. 848 849 850.. data:: XML_ERROR_NOT_SUSPENDED 851 852 An attempt to resume the parser was made when the parser had not been suspended. 853 854 855.. data:: XML_ERROR_ABORTED 856 857 This should not be reported to Python applications. 858 859 860.. data:: XML_ERROR_FINISHED 861 862 The requested operation was made on a parser which was finished parsing input, 863 but isn't allowed. This includes attempts to provide additional input or to 864 stop the parser. 865 866 867.. data:: XML_ERROR_SUSPEND_PE 868 869 870.. rubric:: Footnotes 871 872.. [1] The encoding string included in XML output should conform to the 873 appropriate standards. For example, "UTF-8" is valid, but "UTF8" is 874 not. See https://www.w3.org/TR/2006/REC-xml11-20060816/#NT-EncodingDecl 875 and https://www.iana.org/assignments/character-sets/character-sets.xhtml. 876 877