1 2:mod:`xml.parsers.expat` --- Fast XML parsing using Expat 3========================================================= 4 5.. module:: xml.parsers.expat 6 :synopsis: An interface to the Expat non-validating XML parser. 7.. moduleauthor:: Paul Prescod <paul@prescod.net> 8 9 10.. Markup notes: 11 12 Many of the attributes of the XMLParser objects are callbacks. Since 13 signature information must be presented, these are described using the method 14 directive. Since they are attributes which are set by client code, in-text 15 references to these attributes should be marked using the :member: role. 16 17 18.. warning:: 19 20 The :mod:`pyexpat` module is not secure against maliciously 21 constructed data. If you need to parse untrusted or unauthenticated data see 22 :ref:`xml-vulnerabilities`. 23 24 25.. versionadded:: 2.0 26 27.. index:: single: Expat 28 29The :mod:`xml.parsers.expat` module is a Python interface to the Expat 30non-validating XML parser. The module provides a single extension type, 31:class:`xmlparser`, that represents the current state of an XML parser. After 32an :class:`xmlparser` object has been created, various attributes of the object 33can be set to handler functions. When an XML document is then fed to the 34parser, the handler functions are called for the character data and markup in 35the XML document. 36 37.. index:: module: pyexpat 38 39This module uses the :mod:`pyexpat` module to provide access to the Expat 40parser. Direct use of the :mod:`pyexpat` module is deprecated. 41 42This module provides one exception and one type object: 43 44 45.. exception:: ExpatError 46 47 The exception raised when Expat reports an error. See section 48 :ref:`expaterror-objects` for more information on interpreting Expat errors. 49 50 51.. exception:: error 52 53 Alias for :exc:`ExpatError`. 54 55 56.. data:: XMLParserType 57 58 The type of the return values from the :func:`ParserCreate` function. 59 60The :mod:`xml.parsers.expat` module contains two functions: 61 62 63.. function:: ErrorString(errno) 64 65 Returns an explanatory string for a given error number *errno*. 66 67 68.. function:: ParserCreate([encoding[, namespace_separator]]) 69 70 Creates and returns a new :class:`xmlparser` object. *encoding*, if specified, 71 must be a string naming the encoding used by the XML data. Expat doesn't 72 support as many encodings as Python does, and its repertoire of encodings can't 73 be extended; it supports UTF-8, UTF-16, ISO-8859-1 (Latin1), and ASCII. If 74 *encoding* [1]_ is given it will override the implicit or explicit encoding of the 75 document. 76 77 Expat can optionally do XML namespace processing for you, enabled by providing a 78 value for *namespace_separator*. The value must be a one-character string; a 79 :exc:`ValueError` will be raised if the string has an illegal length (``None`` 80 is considered the same as omission). When namespace processing is enabled, 81 element type names and attribute names that belong to a namespace will be 82 expanded. The element name passed to the element handlers 83 :attr:`StartElementHandler` and :attr:`EndElementHandler` will be the 84 concatenation of the namespace URI, the namespace separator character, and the 85 local part of the name. If the namespace separator is a zero byte (``chr(0)``) 86 then the namespace URI and the local part will be concatenated without any 87 separator. 88 89 For example, if *namespace_separator* is set to a space character (``' '``) and 90 the following document is parsed: 91 92 .. code-block:: xml 93 94 <?xml version="1.0"?> 95 <root xmlns = "http://default-namespace.org/" 96 xmlns:py = "http://www.python.org/ns/"> 97 <py:elem1 /> 98 <elem2 xmlns="" /> 99 </root> 100 101 :attr:`StartElementHandler` will receive the following strings for each 102 element:: 103 104 http://default-namespace.org/ root 105 http://www.python.org/ns/ elem1 106 elem2 107 108 Due to limitations in the ``Expat`` library used by :mod:`pyexpat`, 109 the :class:`xmlparser` instance returned can only be used to parse a single 110 XML document. Call ``ParserCreate`` for each document to provide unique 111 parser instances. 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 .. versionadded:: 2.1 165 166 167.. method:: xmlparser.ExternalEntityParserCreate(context[, encoding]) 168 169 Create a "child" parser which can be used to parse an external parsed entity 170 referred to by content parsed by the parent parser. The *context* parameter 171 should be the string passed to the :meth:`ExternalEntityRefHandler` handler 172 function, described below. The child parser is created with the 173 :attr:`ordered_attributes`, :attr:`returns_unicode` and 174 :attr:`specified_attributes` set to the values of this parser. 175 176.. method:: xmlparser.SetParamEntityParsing(flag) 177 178 Control parsing of parameter entities (including the external DTD subset). 179 Possible *flag* values are :const:`XML_PARAM_ENTITY_PARSING_NEVER`, 180 :const:`XML_PARAM_ENTITY_PARSING_UNLESS_STANDALONE` and 181 :const:`XML_PARAM_ENTITY_PARSING_ALWAYS`. Return true if setting the flag 182 was successful. 183 184.. method:: xmlparser.UseForeignDTD([flag]) 185 186 Calling this with a true value for *flag* (the default) will cause Expat to call 187 the :attr:`ExternalEntityRefHandler` with :const:`None` for all arguments to 188 allow an alternate DTD to be loaded. If the document does not contain a 189 document type declaration, the :attr:`ExternalEntityRefHandler` will still be 190 called, but the :attr:`StartDoctypeDeclHandler` and 191 :attr:`EndDoctypeDeclHandler` will not be called. 192 193 Passing a false value for *flag* will cancel a previous call that passed a true 194 value, but otherwise has no effect. 195 196 This method can only be called before the :meth:`Parse` or :meth:`ParseFile` 197 methods are called; calling it after either of those have been called causes 198 :exc:`ExpatError` to be raised with the :attr:`code` attribute set to 199 :const:`errors.XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING`. 200 201 .. versionadded:: 2.3 202 203:class:`xmlparser` objects have the following attributes: 204 205 206.. attribute:: xmlparser.buffer_size 207 208 The size of the buffer used when :attr:`buffer_text` is true. 209 A new buffer size can be set by assigning a new integer value 210 to this attribute. 211 When the size is changed, the buffer will be flushed. 212 213 .. versionadded:: 2.3 214 215 .. versionchanged:: 2.6 216 The buffer size can now be changed. 217 218.. attribute:: xmlparser.buffer_text 219 220 Setting this to true causes the :class:`xmlparser` object to buffer textual 221 content returned by Expat to avoid multiple calls to the 222 :meth:`CharacterDataHandler` callback whenever possible. This can improve 223 performance substantially since Expat normally breaks character data into chunks 224 at every line ending. This attribute is false by default, and may be changed at 225 any time. 226 227 .. versionadded:: 2.3 228 229 230.. attribute:: xmlparser.buffer_used 231 232 If :attr:`buffer_text` is enabled, the number of bytes stored in the buffer. 233 These bytes represent UTF-8 encoded text. This attribute has no meaningful 234 interpretation when :attr:`buffer_text` is false. 235 236 .. versionadded:: 2.3 237 238 239.. attribute:: xmlparser.ordered_attributes 240 241 Setting this attribute to a non-zero integer causes the attributes to be 242 reported as a list rather than a dictionary. The attributes are presented in 243 the order found in the document text. For each attribute, two list entries are 244 presented: the attribute name and the attribute value. (Older versions of this 245 module also used this format.) By default, this attribute is false; it may be 246 changed at any time. 247 248 .. versionadded:: 2.1 249 250 251.. attribute:: xmlparser.returns_unicode 252 253 If this attribute is set to a non-zero integer, the handler functions will be 254 passed Unicode strings. If :attr:`returns_unicode` is :const:`False`, 8-bit 255 strings containing UTF-8 encoded data will be passed to the handlers. This is 256 :const:`True` by default when Python is built with Unicode support. 257 258 .. versionchanged:: 1.6 259 Can be changed at any time to affect the result type. 260 261 262.. attribute:: xmlparser.specified_attributes 263 264 If set to a non-zero integer, the parser will report only those attributes which 265 were specified in the document instance and not those which were derived from 266 attribute declarations. Applications which set this need to be especially 267 careful to use what additional information is available from the declarations as 268 needed to comply with the standards for the behavior of XML processors. By 269 default, this attribute is false; it may be changed at any time. 270 271 .. versionadded:: 2.1 272 273The following attributes contain values relating to the most recent error 274encountered by an :class:`xmlparser` object, and will only have correct values 275once a call to :meth:`Parse` or :meth:`ParseFile` has raised an 276:exc:`xml.parsers.expat.ExpatError` exception. 277 278 279.. attribute:: xmlparser.ErrorByteIndex 280 281 Byte index at which an error occurred. 282 283 284.. attribute:: xmlparser.ErrorCode 285 286 Numeric code specifying the problem. This value can be passed to the 287 :func:`ErrorString` function, or compared to one of the constants defined in the 288 ``errors`` object. 289 290 291.. attribute:: xmlparser.ErrorColumnNumber 292 293 Column number at which an error occurred. 294 295 296.. attribute:: xmlparser.ErrorLineNumber 297 298 Line number at which an error occurred. 299 300The following attributes contain values relating to the current parse location 301in an :class:`xmlparser` object. During a callback reporting a parse event they 302indicate the location of the first of the sequence of characters that generated 303the event. When called outside of a callback, the position indicated will be 304just past the last parse event (regardless of whether there was an associated 305callback). 306 307.. versionadded:: 2.4 308 309 310.. attribute:: xmlparser.CurrentByteIndex 311 312 Current byte index in the parser input. 313 314 315.. attribute:: xmlparser.CurrentColumnNumber 316 317 Current column number in the parser input. 318 319 320.. attribute:: xmlparser.CurrentLineNumber 321 322 Current line number in the parser input. 323 324Here is the list of handlers that can be set. To set a handler on an 325:class:`xmlparser` object *o*, use ``o.handlername = func``. *handlername* must 326be taken from the following list, and *func* must be a callable object accepting 327the correct number of arguments. The arguments are all strings, unless 328otherwise stated. 329 330 331.. method:: xmlparser.XmlDeclHandler(version, encoding, standalone) 332 333 Called when the XML declaration is parsed. The XML declaration is the 334 (optional) declaration of the applicable version of the XML recommendation, the 335 encoding of the document text, and an optional "standalone" declaration. 336 *version* and *encoding* will be strings of the type dictated by the 337 :attr:`returns_unicode` attribute, and *standalone* will be ``1`` if the 338 document is declared standalone, ``0`` if it is declared not to be standalone, 339 or ``-1`` if the standalone clause was omitted. This is only available with 340 Expat version 1.95.0 or newer. 341 342 .. versionadded:: 2.1 343 344 345.. method:: xmlparser.StartDoctypeDeclHandler(doctypeName, systemId, publicId, has_internal_subset) 346 347 Called when Expat begins parsing the document type declaration (``<!DOCTYPE 348 ...``). The *doctypeName* is provided exactly as presented. The *systemId* and 349 *publicId* parameters give the system and public identifiers if specified, or 350 ``None`` if omitted. *has_internal_subset* will be true if the document 351 contains and internal document declaration subset. This requires Expat version 352 1.2 or newer. 353 354 355.. method:: xmlparser.EndDoctypeDeclHandler() 356 357 Called when Expat is done parsing the document type declaration. This requires 358 Expat version 1.2 or newer. 359 360 361.. method:: xmlparser.ElementDeclHandler(name, model) 362 363 Called once for each element type declaration. *name* is the name of the 364 element type, and *model* is a representation of the content model. 365 366 367.. method:: xmlparser.AttlistDeclHandler(elname, attname, type, default, required) 368 369 Called for each declared attribute for an element type. If an attribute list 370 declaration declares three attributes, this handler is called three times, once 371 for each attribute. *elname* is the name of the element to which the 372 declaration applies and *attname* is the name of the attribute declared. The 373 attribute type is a string passed as *type*; the possible values are 374 ``'CDATA'``, ``'ID'``, ``'IDREF'``, ... *default* gives the default value for 375 the attribute used when the attribute is not specified by the document instance, 376 or ``None`` if there is no default value (``#IMPLIED`` values). If the 377 attribute is required to be given in the document instance, *required* will be 378 true. This requires Expat version 1.95.0 or newer. 379 380 381.. method:: xmlparser.StartElementHandler(name, attributes) 382 383 Called for the start of every element. *name* is a string containing the 384 element name, and *attributes* is a dictionary mapping attribute names to their 385 values. 386 387 388.. method:: xmlparser.EndElementHandler(name) 389 390 Called for the end of every element. 391 392 393.. method:: xmlparser.ProcessingInstructionHandler(target, data) 394 395 Called for every processing instruction. 396 397 398.. method:: xmlparser.CharacterDataHandler(data) 399 400 Called for character data. This will be called for normal character data, CDATA 401 marked content, and ignorable whitespace. Applications which must distinguish 402 these cases can use the :attr:`StartCdataSectionHandler`, 403 :attr:`EndCdataSectionHandler`, and :attr:`ElementDeclHandler` callbacks to 404 collect the required information. 405 406 407.. method:: xmlparser.UnparsedEntityDeclHandler(entityName, base, systemId, publicId, notationName) 408 409 Called for unparsed (NDATA) entity declarations. This is only present for 410 version 1.2 of the Expat library; for more recent versions, use 411 :attr:`EntityDeclHandler` instead. (The underlying function in the Expat 412 library has been declared obsolete.) 413 414 415.. method:: xmlparser.EntityDeclHandler(entityName, is_parameter_entity, value, base, systemId, publicId, notationName) 416 417 Called for all entity declarations. For parameter and internal entities, 418 *value* will be a string giving the declared contents of the entity; this will 419 be ``None`` for external entities. The *notationName* parameter will be 420 ``None`` for parsed entities, and the name of the notation for unparsed 421 entities. *is_parameter_entity* will be true if the entity is a parameter entity 422 or false for general entities (most applications only need to be concerned with 423 general entities). This is only available starting with version 1.95.0 of the 424 Expat library. 425 426 .. versionadded:: 2.1 427 428 429.. method:: xmlparser.NotationDeclHandler(notationName, base, systemId, publicId) 430 431 Called for notation declarations. *notationName*, *base*, and *systemId*, and 432 *publicId* are strings if given. If the public identifier is omitted, 433 *publicId* will be ``None``. 434 435 436.. method:: xmlparser.StartNamespaceDeclHandler(prefix, uri) 437 438 Called when an element contains a namespace declaration. Namespace declarations 439 are processed before the :attr:`StartElementHandler` is called for the element 440 on which declarations are placed. 441 442 443.. method:: xmlparser.EndNamespaceDeclHandler(prefix) 444 445 Called when the closing tag is reached for an element that contained a 446 namespace declaration. This is called once for each namespace declaration on 447 the element in the reverse of the order for which the 448 :attr:`StartNamespaceDeclHandler` was called to indicate the start of each 449 namespace declaration's scope. Calls to this handler are made after the 450 corresponding :attr:`EndElementHandler` for the end of the element. 451 452 453.. method:: xmlparser.CommentHandler(data) 454 455 Called for comments. *data* is the text of the comment, excluding the leading 456 ``'<!-``\ ``-'`` and trailing ``'-``\ ``->'``. 457 458 459.. method:: xmlparser.StartCdataSectionHandler() 460 461 Called at the start of a CDATA section. This and :attr:`EndCdataSectionHandler` 462 are needed to be able to identify the syntactical start and end for CDATA 463 sections. 464 465 466.. method:: xmlparser.EndCdataSectionHandler() 467 468 Called at the end of a CDATA section. 469 470 471.. method:: xmlparser.DefaultHandler(data) 472 473 Called for any characters in the XML document for which no applicable handler 474 has been specified. This means characters that are part of a construct which 475 could be reported, but for which no handler has been supplied. 476 477 478.. method:: xmlparser.DefaultHandlerExpand(data) 479 480 This is the same as the :func:`DefaultHandler`, but doesn't inhibit expansion 481 of internal entities. The entity reference will not be passed to the default 482 handler. 483 484 485.. method:: xmlparser.NotStandaloneHandler() 486 487 Called if the XML document hasn't been declared as being a standalone document. 488 This happens when there is an external subset or a reference to a parameter 489 entity, but the XML declaration does not set standalone to ``yes`` in an XML 490 declaration. If this handler returns ``0``, then the parser will raise an 491 :const:`XML_ERROR_NOT_STANDALONE` error. If this handler is not set, no 492 exception is raised by the parser for this condition. 493 494 495.. method:: xmlparser.ExternalEntityRefHandler(context, base, systemId, publicId) 496 497 Called for references to external entities. *base* is the current base, as set 498 by a previous call to :meth:`SetBase`. The public and system identifiers, 499 *systemId* and *publicId*, are strings if given; if the public identifier is not 500 given, *publicId* will be ``None``. The *context* value is opaque and should 501 only be used as described below. 502 503 For external entities to be parsed, this handler must be implemented. It is 504 responsible for creating the sub-parser using 505 ``ExternalEntityParserCreate(context)``, initializing it with the appropriate 506 callbacks, and parsing the entity. This handler should return an integer; if it 507 returns ``0``, the parser will raise an 508 :const:`XML_ERROR_EXTERNAL_ENTITY_HANDLING` error, otherwise parsing will 509 continue. 510 511 If this handler is not provided, external entities are reported by the 512 :attr:`DefaultHandler` callback, if provided. 513 514 515.. _expaterror-objects: 516 517ExpatError Exceptions 518--------------------- 519 520.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org> 521 522 523:exc:`ExpatError` exceptions have a number of interesting attributes: 524 525 526.. attribute:: ExpatError.code 527 528 Expat's internal error number for the specific error. This will match one of 529 the constants defined in the ``errors`` object from this module. 530 531 .. versionadded:: 2.1 532 533 534.. attribute:: ExpatError.lineno 535 536 Line number on which the error was detected. The first line is numbered ``1``. 537 538 .. versionadded:: 2.1 539 540 541.. attribute:: ExpatError.offset 542 543 Character offset into the line where the error occurred. The first column is 544 numbered ``0``. 545 546 .. versionadded:: 2.1 547 548 549.. _expat-example: 550 551Example 552------- 553 554The following program defines three handlers that just print out their 555arguments. :: 556 557 import xml.parsers.expat 558 559 # 3 handler functions 560 def start_element(name, attrs): 561 print 'Start element:', name, attrs 562 def end_element(name): 563 print 'End element:', name 564 def char_data(data): 565 print 'Character data:', repr(data) 566 567 p = xml.parsers.expat.ParserCreate() 568 569 p.StartElementHandler = start_element 570 p.EndElementHandler = end_element 571 p.CharacterDataHandler = char_data 572 573 p.Parse("""<?xml version="1.0"?> 574 <parent id="top"><child1 name="paul">Text goes here</child1> 575 <child2 name="fred">More text</child2> 576 </parent>""", 1) 577 578The output from this program is:: 579 580 Start element: parent {'id': 'top'} 581 Start element: child1 {'name': 'paul'} 582 Character data: 'Text goes here' 583 End element: child1 584 Character data: '\n' 585 Start element: child2 {'name': 'fred'} 586 Character data: 'More text' 587 End element: child2 588 Character data: '\n' 589 End element: parent 590 591 592.. _expat-content-models: 593 594Content Model Descriptions 595-------------------------- 596 597.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org> 598 599 600Content models are described using nested tuples. Each tuple contains four 601values: the type, the quantifier, the name, and a tuple of children. Children 602are simply additional content model descriptions. 603 604The values of the first two fields are constants defined in the ``model`` object 605of the :mod:`xml.parsers.expat` module. These constants can be collected in two 606groups: the model type group and the quantifier group. 607 608The constants in the model type group are: 609 610 611.. data:: XML_CTYPE_ANY 612 :noindex: 613 614 The element named by the model name was declared to have a content model of 615 ``ANY``. 616 617 618.. data:: XML_CTYPE_CHOICE 619 :noindex: 620 621 The named element allows a choice from a number of options; this is used for 622 content models such as ``(A | B | C)``. 623 624 625.. data:: XML_CTYPE_EMPTY 626 :noindex: 627 628 Elements which are declared to be ``EMPTY`` have this model type. 629 630 631.. data:: XML_CTYPE_MIXED 632 :noindex: 633 634 635.. data:: XML_CTYPE_NAME 636 :noindex: 637 638 639.. data:: XML_CTYPE_SEQ 640 :noindex: 641 642 Models which represent a series of models which follow one after the other are 643 indicated with this model type. This is used for models such as ``(A, B, C)``. 644 645The constants in the quantifier group are: 646 647 648.. data:: XML_CQUANT_NONE 649 :noindex: 650 651 No modifier is given, so it can appear exactly once, as for ``A``. 652 653 654.. data:: XML_CQUANT_OPT 655 :noindex: 656 657 The model is optional: it can appear once or not at all, as for ``A?``. 658 659 660.. data:: XML_CQUANT_PLUS 661 :noindex: 662 663 The model must occur one or more times (like ``A+``). 664 665 666.. data:: XML_CQUANT_REP 667 :noindex: 668 669 The model must occur zero or more times, as for ``A*``. 670 671 672.. _expat-errors: 673 674Expat error constants 675--------------------- 676 677The following constants are provided in the ``errors`` object of the 678:mod:`xml.parsers.expat` module. These constants are useful in interpreting 679some of the attributes of the :exc:`ExpatError` exception objects raised when an 680error has occurred. 681 682The ``errors`` object has the following attributes: 683 684 685.. data:: XML_ERROR_ASYNC_ENTITY 686 :noindex: 687 688 689.. data:: XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF 690 :noindex: 691 692 An entity reference in an attribute value referred to an external entity instead 693 of an internal entity. 694 695 696.. data:: XML_ERROR_BAD_CHAR_REF 697 :noindex: 698 699 A character reference referred to a character which is illegal in XML (for 700 example, character ``0``, or '``�``'). 701 702 703.. data:: XML_ERROR_BINARY_ENTITY_REF 704 :noindex: 705 706 An entity reference referred to an entity which was declared with a notation, so 707 cannot be parsed. 708 709 710.. data:: XML_ERROR_DUPLICATE_ATTRIBUTE 711 :noindex: 712 713 An attribute was used more than once in a start tag. 714 715 716.. data:: XML_ERROR_INCORRECT_ENCODING 717 :noindex: 718 719 720.. data:: XML_ERROR_INVALID_TOKEN 721 :noindex: 722 723 Raised when an input byte could not properly be assigned to a character; for 724 example, a NUL byte (value ``0``) in a UTF-8 input stream. 725 726 727.. data:: XML_ERROR_JUNK_AFTER_DOC_ELEMENT 728 :noindex: 729 730 Something other than whitespace occurred after the document element. 731 732 733.. data:: XML_ERROR_MISPLACED_XML_PI 734 :noindex: 735 736 An XML declaration was found somewhere other than the start of the input data. 737 738 739.. data:: XML_ERROR_NO_ELEMENTS 740 :noindex: 741 742 The document contains no elements (XML requires all documents to contain exactly 743 one top-level element).. 744 745 746.. data:: XML_ERROR_NO_MEMORY 747 :noindex: 748 749 Expat was not able to allocate memory internally. 750 751 752.. data:: XML_ERROR_PARAM_ENTITY_REF 753 :noindex: 754 755 A parameter entity reference was found where it was not allowed. 756 757 758.. data:: XML_ERROR_PARTIAL_CHAR 759 :noindex: 760 761 An incomplete character was found in the input. 762 763 764.. data:: XML_ERROR_RECURSIVE_ENTITY_REF 765 :noindex: 766 767 An entity reference contained another reference to the same entity; possibly via 768 a different name, and possibly indirectly. 769 770 771.. data:: XML_ERROR_SYNTAX 772 :noindex: 773 774 Some unspecified syntax error was encountered. 775 776 777.. data:: XML_ERROR_TAG_MISMATCH 778 :noindex: 779 780 An end tag did not match the innermost open start tag. 781 782 783.. data:: XML_ERROR_UNCLOSED_TOKEN 784 :noindex: 785 786 Some token (such as a start tag) was not closed before the end of the stream or 787 the next token was encountered. 788 789 790.. data:: XML_ERROR_UNDEFINED_ENTITY 791 :noindex: 792 793 A reference was made to an entity which was not defined. 794 795 796.. data:: XML_ERROR_UNKNOWN_ENCODING 797 :noindex: 798 799 The document encoding is not supported by Expat. 800 801 802.. data:: XML_ERROR_UNCLOSED_CDATA_SECTION 803 :noindex: 804 805 A CDATA marked section was not closed. 806 807 808.. data:: XML_ERROR_EXTERNAL_ENTITY_HANDLING 809 :noindex: 810 811 812.. data:: XML_ERROR_NOT_STANDALONE 813 :noindex: 814 815 The parser determined that the document was not "standalone" though it declared 816 itself to be in the XML declaration, and the :attr:`NotStandaloneHandler` was 817 set and returned ``0``. 818 819 820.. data:: XML_ERROR_UNEXPECTED_STATE 821 :noindex: 822 823 824.. data:: XML_ERROR_ENTITY_DECLARED_IN_PE 825 :noindex: 826 827 828.. data:: XML_ERROR_FEATURE_REQUIRES_XML_DTD 829 :noindex: 830 831 An operation was requested that requires DTD support to be compiled in, but 832 Expat was configured without DTD support. This should never be reported by a 833 standard build of the :mod:`xml.parsers.expat` module. 834 835 836.. data:: XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING 837 :noindex: 838 839 A behavioral change was requested after parsing started that can only be changed 840 before parsing has started. This is (currently) only raised by 841 :meth:`UseForeignDTD`. 842 843 844.. data:: XML_ERROR_UNBOUND_PREFIX 845 :noindex: 846 847 An undeclared prefix was found when namespace processing was enabled. 848 849 850.. data:: XML_ERROR_UNDECLARING_PREFIX 851 :noindex: 852 853 The document attempted to remove the namespace declaration associated with a 854 prefix. 855 856 857.. data:: XML_ERROR_INCOMPLETE_PE 858 :noindex: 859 860 A parameter entity contained incomplete markup. 861 862 863.. data:: XML_ERROR_XML_DECL 864 :noindex: 865 866 The document contained no document element at all. 867 868 869.. data:: XML_ERROR_TEXT_DECL 870 :noindex: 871 872 There was an error parsing a text declaration in an external entity. 873 874 875.. data:: XML_ERROR_PUBLICID 876 :noindex: 877 878 Characters were found in the public id that are not allowed. 879 880 881.. data:: XML_ERROR_SUSPENDED 882 :noindex: 883 884 The requested operation was made on a suspended parser, but isn't allowed. This 885 includes attempts to provide additional input or to stop the parser. 886 887 888.. data:: XML_ERROR_NOT_SUSPENDED 889 :noindex: 890 891 An attempt to resume the parser was made when the parser had not been suspended. 892 893 894.. data:: XML_ERROR_ABORTED 895 :noindex: 896 897 This should not be reported to Python applications. 898 899 900.. data:: XML_ERROR_FINISHED 901 :noindex: 902 903 The requested operation was made on a parser which was finished parsing input, 904 but isn't allowed. This includes attempts to provide additional input or to 905 stop the parser. 906 907 908.. data:: XML_ERROR_SUSPEND_PE 909 :noindex: 910 911 912.. rubric:: Footnotes 913 914.. [1] The encoding string included in XML output should conform to the 915 appropriate standards. For example, "UTF-8" is valid, but "UTF8" is 916 not. See https://www.w3.org/TR/2006/REC-xml11-20060816/#NT-EncodingDecl 917 and https://www.iana.org/assignments/character-sets/character-sets.xhtml. 918 919