655 lines
25 KiB
TeX
655 lines
25 KiB
TeX
\section{\module{xml.parsers.expat} ---
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Fast XML parsing using Expat}
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% Markup notes:
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%
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% Many of the attributes of the XMLParser objects are callbacks.
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% Since signature information must be presented, these are described
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% using the methoddesc environment. Since they are attributes which
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% are set by client code, in-text references to these attributes
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% should be marked using the \member macro and should not include the
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% parentheses used when marking functions and methods.
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\declaremodule{standard}{xml.parsers.expat}
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\modulesynopsis{An interface to the Expat non-validating XML parser.}
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\moduleauthor{Paul Prescod}{paul@prescod.net}
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\versionadded{2.0}
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The \module{xml.parsers.expat} module is a Python interface to the
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Expat\index{Expat} non-validating XML parser.
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The module provides a single extension type, \class{xmlparser}, that
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represents the current state of an XML parser. After an
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\class{xmlparser} object has been created, various attributes of the object
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can be set to handler functions. When an XML document is then fed to
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the parser, the handler functions are called for the character data
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and markup in the XML document.
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This module uses the \module{pyexpat}\refbimodindex{pyexpat} module to
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provide access to the Expat parser. Direct use of the
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\module{pyexpat} module is deprecated.
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This module provides one exception and one type object:
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\begin{excdesc}{ExpatError}
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The exception raised when Expat reports an error. See section
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\ref{expaterror-objects}, ``ExpatError Exceptions,'' for more
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information on interpreting Expat errors.
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\end{excdesc}
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\begin{excdesc}{error}
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Alias for \exception{ExpatError}.
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\end{excdesc}
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\begin{datadesc}{XMLParserType}
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The type of the return values from the \function{ParserCreate()}
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function.
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\end{datadesc}
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The \module{xml.parsers.expat} module contains two functions:
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\begin{funcdesc}{ErrorString}{errno}
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Returns an explanatory string for a given error number \var{errno}.
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\end{funcdesc}
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\begin{funcdesc}{ParserCreate}{\optional{encoding\optional{,
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namespace_separator}}}
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Creates and returns a new \class{xmlparser} object.
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\var{encoding}, if specified, must be a string naming the encoding
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used by the XML data. Expat doesn't support as many encodings as
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Python does, and its repertoire of encodings can't be extended; it
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supports UTF-8, UTF-16, ISO-8859-1 (Latin1), and ASCII. If
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\var{encoding} is given it will override the implicit or explicit
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encoding of the document.
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Expat can optionally do XML namespace processing for you, enabled by
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providing a value for \var{namespace_separator}. The value must be a
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one-character string; a \exception{ValueError} will be raised if the
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string has an illegal length (\code{None} is considered the same as
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omission). When namespace processing is enabled, element type names
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and attribute names that belong to a namespace will be expanded. The
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element name passed to the element handlers
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\member{StartElementHandler} and \member{EndElementHandler}
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will be the concatenation of the namespace URI, the namespace
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separator character, and the local part of the name. If the namespace
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separator is a zero byte (\code{chr(0)}) then the namespace URI and
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the local part will be concatenated without any separator.
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For example, if \var{namespace_separator} is set to a space character
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(\character{ }) and the following document is parsed:
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\begin{verbatim}
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<?xml version="1.0"?>
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<root xmlns = "http://default-namespace.org/"
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xmlns:py = "http://www.python.org/ns/">
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<py:elem1 />
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<elem2 xmlns="" />
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</root>
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\end{verbatim}
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\member{StartElementHandler} will receive the following strings
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for each element:
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\begin{verbatim}
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http://default-namespace.org/ root
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http://www.python.org/ns/ elem1
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elem2
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\end{verbatim}
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\end{funcdesc}
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\begin{seealso}
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\seetitle[http://www.libexpat.org/]{The Expat XML Parser}
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{Home page of the Expat project.}
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\end{seealso}
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\subsection{XMLParser Objects \label{xmlparser-objects}}
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\class{xmlparser} objects have the following methods:
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\begin{methoddesc}[xmlparser]{Parse}{data\optional{, isfinal}}
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Parses the contents of the string \var{data}, calling the appropriate
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handler functions to process the parsed data. \var{isfinal} must be
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true on the final call to this method. \var{data} can be the empty
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string at any time.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{ParseFile}{file}
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Parse XML data reading from the object \var{file}. \var{file} only
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needs to provide the \method{read(\var{nbytes})} method, returning the
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empty string when there's no more data.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{SetBase}{base}
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Sets the base to be used for resolving relative URIs in system
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identifiers in declarations. Resolving relative identifiers is left
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to the application: this value will be passed through as the
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\var{base} argument to the \function{ExternalEntityRefHandler},
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\function{NotationDeclHandler}, and
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\function{UnparsedEntityDeclHandler} functions.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{GetBase}{}
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Returns a string containing the base set by a previous call to
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\method{SetBase()}, or \code{None} if
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\method{SetBase()} hasn't been called.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{GetInputContext}{}
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Returns the input data that generated the current event as a string.
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The data is in the encoding of the entity which contains the text.
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When called while an event handler is not active, the return value is
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\code{None}.
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\versionadded{2.1}
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{ExternalEntityParserCreate}{context\optional{,
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encoding}}
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Create a ``child'' parser which can be used to parse an external
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parsed entity referred to by content parsed by the parent parser. The
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\var{context} parameter should be the string passed to the
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\method{ExternalEntityRefHandler()} handler function, described below.
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The child parser is created with the \member{ordered_attributes},
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\member{returns_unicode} and \member{specified_attributes} set to the
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values of this parser.
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\end{methoddesc}
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\class{xmlparser} objects have the following attributes:
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\begin{memberdesc}[xmlparser]{buffer_size}
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The size of the buffer used when \member{buffer_text} is true. This
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value cannot be changed at this time.
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\versionadded{2.3}
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{buffer_text}
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Setting this to true causes the \class{xmlparser} object to buffer
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textual content returned by Expat to avoid multiple calls to the
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\method{CharacterDataHandler()} callback whenever possible. This can
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improve performance substantially since Expat normally breaks
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character data into chunks at every line ending. This attribute is
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false by default, and may be changed at any time.
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\versionadded{2.3}
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{buffer_used}
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If \member{buffer_text} is enabled, the number of bytes stored in the
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buffer. These bytes represent UTF-8 encoded text. This attribute has
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no meaningful interpretation when \member{buffer_text} is false.
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\versionadded{2.3}
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{ordered_attributes}
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Setting this attribute to a non-zero integer causes the attributes to
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be reported as a list rather than a dictionary. The attributes are
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presented in the order found in the document text. For each
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attribute, two list entries are presented: the attribute name and the
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attribute value. (Older versions of this module also used this
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format.) By default, this attribute is false; it may be changed at
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any time.
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\versionadded{2.1}
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{returns_unicode}
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If this attribute is set to a non-zero integer, the handler functions
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will be passed Unicode strings. If \member{returns_unicode} is 0,
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8-bit strings containing UTF-8 encoded data will be passed to the
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handlers.
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\versionchanged[Can be changed at any time to affect the result
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type]{1.6}
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{specified_attributes}
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If set to a non-zero integer, the parser will report only those
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attributes which were specified in the document instance and not those
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which were derived from attribute declarations. Applications which
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set this need to be especially careful to use what additional
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information is available from the declarations as needed to comply
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with the standards for the behavior of XML processors. By default,
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this attribute is false; it may be changed at any time.
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\versionadded{2.1}
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\end{memberdesc}
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The following attributes contain values relating to the most recent
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error encountered by an \class{xmlparser} object, and will only have
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correct values once a call to \method{Parse()} or \method{ParseFile()}
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has raised a \exception{xml.parsers.expat.ExpatError} exception.
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\begin{memberdesc}[xmlparser]{ErrorByteIndex}
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Byte index at which an error occurred.
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{ErrorCode}
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Numeric code specifying the problem. This value can be passed to the
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\function{ErrorString()} function, or compared to one of the constants
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defined in the \code{errors} object.
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{ErrorColumnNumber}
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Column number at which an error occurred.
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\end{memberdesc}
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\begin{memberdesc}[xmlparser]{ErrorLineNumber}
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Line number at which an error occurred.
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\end{memberdesc}
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Here is the list of handlers that can be set. To set a handler on an
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\class{xmlparser} object \var{o}, use
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\code{\var{o}.\var{handlername} = \var{func}}. \var{handlername} must
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be taken from the following list, and \var{func} must be a callable
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object accepting the correct number of arguments. The arguments are
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all strings, unless otherwise stated.
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\begin{methoddesc}[xmlparser]{XmlDeclHandler}{version, encoding, standalone}
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Called when the XML declaration is parsed. The XML declaration is the
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(optional) declaration of the applicable version of the XML
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recommendation, the encoding of the document text, and an optional
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``standalone'' declaration. \var{version} and \var{encoding} will be
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strings of the type dictated by the \member{returns_unicode}
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attribute, and \var{standalone} will be \code{1} if the document is
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declared standalone, \code{0} if it is declared not to be standalone,
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or \code{-1} if the standalone clause was omitted.
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This is only available with Expat version 1.95.0 or newer.
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\versionadded{2.1}
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{StartDoctypeDeclHandler}{doctypeName,
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systemId, publicId,
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has_internal_subset}
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Called when Expat begins parsing the document type declaration
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(\code{<!DOCTYPE \ldots}). The \var{doctypeName} is provided exactly
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as presented. The \var{systemId} and \var{publicId} parameters give
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the system and public identifiers if specified, or \code{None} if
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omitted. \var{has_internal_subset} will be true if the document
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contains and internal document declaration subset.
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This requires Expat version 1.2 or newer.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{EndDoctypeDeclHandler}{}
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Called when Expat is done parsing the document type delaration.
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This requires Expat version 1.2 or newer.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{ElementDeclHandler}{name, model}
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Called once for each element type declaration. \var{name} is the name
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of the element type, and \var{model} is a representation of the
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content model.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{AttlistDeclHandler}{elname, attname,
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type, default, required}
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Called for each declared attribute for an element type. If an
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attribute list declaration declares three attributes, this handler is
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called three times, once for each attribute. \var{elname} is the name
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of the element to which the declaration applies and \var{attname} is
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the name of the attribute declared. The attribute type is a string
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passed as \var{type}; the possible values are \code{'CDATA'},
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\code{'ID'}, \code{'IDREF'}, ...
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\var{default} gives the default value for the attribute used when the
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attribute is not specified by the document instance, or \code{None} if
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there is no default value (\code{\#IMPLIED} values). If the attribute
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is required to be given in the document instance, \var{required} will
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be true.
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This requires Expat version 1.95.0 or newer.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{StartElementHandler}{name, attributes}
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Called for the start of every element. \var{name} is a string
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containing the element name, and \var{attributes} is a dictionary
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mapping attribute names to their values.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{EndElementHandler}{name}
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Called for the end of every element.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{ProcessingInstructionHandler}{target, data}
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Called for every processing instruction.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{CharacterDataHandler}{data}
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Called for character data. This will be called for normal character
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data, CDATA marked content, and ignorable whitespace. Applications
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which must distinguish these cases can use the
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\member{StartCdataSectionHandler}, \member{EndCdataSectionHandler},
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and \member{ElementDeclHandler} callbacks to collect the required
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information.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{UnparsedEntityDeclHandler}{entityName, base,
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systemId, publicId,
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notationName}
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Called for unparsed (NDATA) entity declarations. This is only present
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for version 1.2 of the Expat library; for more recent versions, use
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\member{EntityDeclHandler} instead. (The underlying function in the
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Expat library has been declared obsolete.)
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{EntityDeclHandler}{entityName,
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is_parameter_entity, value,
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base, systemId,
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publicId,
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notationName}
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Called for all entity declarations. For parameter and internal
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entities, \var{value} will be a string giving the declared contents
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of the entity; this will be \code{None} for external entities. The
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\var{notationName} parameter will be \code{None} for parsed entities,
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and the name of the notation for unparsed entities.
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\var{is_parameter_entity} will be true if the entity is a paremeter
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entity or false for general entities (most applications only need to
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be concerned with general entities).
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This is only available starting with version 1.95.0 of the Expat
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library.
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\versionadded{2.1}
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{NotationDeclHandler}{notationName, base,
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systemId, publicId}
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Called for notation declarations. \var{notationName}, \var{base}, and
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\var{systemId}, and \var{publicId} are strings if given. If the
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public identifier is omitted, \var{publicId} will be \code{None}.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{StartNamespaceDeclHandler}{prefix, uri}
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Called when an element contains a namespace declaration. Namespace
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declarations are processed before the \member{StartElementHandler} is
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called for the element on which declarations are placed.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{EndNamespaceDeclHandler}{prefix}
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Called when the closing tag is reached for an element
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that contained a namespace declaration. This is called once for each
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namespace declaration on the element in the reverse of the order for
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which the \member{StartNamespaceDeclHandler} was called to indicate
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the start of each namespace declaration's scope. Calls to this
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handler are made after the corresponding \member{EndElementHandler}
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for the end of the element.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{CommentHandler}{data}
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Called for comments. \var{data} is the text of the comment, excluding
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the leading `\code{<!-}\code{-}' and trailing `\code{-}\code{->}'.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{StartCdataSectionHandler}{}
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Called at the start of a CDATA section. This and
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\member{StartCdataSectionHandler} are needed to be able to identify
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the syntactical start and end for CDATA sections.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{EndCdataSectionHandler}{}
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Called at the end of a CDATA section.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{DefaultHandler}{data}
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Called for any characters in the XML document for
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which no applicable handler has been specified. This means
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characters that are part of a construct which could be reported, but
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for which no handler has been supplied.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{DefaultHandlerExpand}{data}
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This is the same as the \function{DefaultHandler},
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but doesn't inhibit expansion of internal entities.
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The entity reference will not be passed to the default handler.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{NotStandaloneHandler}{} Called if the
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XML document hasn't been declared as being a standalone document.
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This happens when there is an external subset or a reference to a
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parameter entity, but the XML declaration does not set standalone to
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\code{yes} in an XML declaration. If this handler returns \code{0},
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then the parser will throw an \constant{XML_ERROR_NOT_STANDALONE}
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error. If this handler is not set, no exception is raised by the
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parser for this condition.
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\end{methoddesc}
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\begin{methoddesc}[xmlparser]{ExternalEntityRefHandler}{context, base,
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systemId, publicId}
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Called for references to external entities. \var{base} is the current
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base, as set by a previous call to \method{SetBase()}. The public and
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system identifiers, \var{systemId} and \var{publicId}, are strings if
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given; if the public identifier is not given, \var{publicId} will be
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\code{None}. The \var{context} value is opaque and should only be
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used as described below.
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For external entities to be parsed, this handler must be implemented.
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It is responsible for creating the sub-parser using
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\code{ExternalEntityParserCreate(\var{context})}, initializing it with
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the appropriate callbacks, and parsing the entity. This handler
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should return an integer; if it returns \code{0}, the parser will
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throw an \constant{XML_ERROR_EXTERNAL_ENTITY_HANDLING} error,
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otherwise parsing will continue.
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If this handler is not provided, external entities are reported by the
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\member{DefaultHandler} callback, if provided.
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\end{methoddesc}
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\subsection{ExpatError Exceptions \label{expaterror-objects}}
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\sectionauthor{Fred L. Drake, Jr.}{fdrake@acm.org}
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\exception{ExpatError} exceptions have a number of interesting
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attributes:
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\begin{memberdesc}[ExpatError]{code}
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Expat's internal error number for the specific error. This will
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match one of the constants defined in the \code{errors} object from
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this module.
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\versionadded{2.1}
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\end{memberdesc}
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\begin{memberdesc}[ExpatError]{lineno}
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Line number on which the error was detected. The first line is
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numbered \code{1}.
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\versionadded{2.1}
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\end{memberdesc}
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\begin{memberdesc}[ExpatError]{offset}
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Character offset into the line where the error occurred. The first
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column is numbered \code{0}.
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\versionadded{2.1}
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\end{memberdesc}
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\subsection{Example \label{expat-example}}
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The following program defines three handlers that just print out their
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arguments.
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\begin{verbatim}
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import xml.parsers.expat
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# 3 handler functions
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def start_element(name, attrs):
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print 'Start element:', name, attrs
|
|
def end_element(name):
|
|
print 'End element:', name
|
|
def char_data(data):
|
|
print 'Character data:', repr(data)
|
|
|
|
p = xml.parsers.expat.ParserCreate()
|
|
|
|
p.StartElementHandler = start_element
|
|
p.EndElementHandler = end_element
|
|
p.CharacterDataHandler = char_data
|
|
|
|
p.Parse("""<?xml version="1.0"?>
|
|
<parent id="top"><child1 name="paul">Text goes here</child1>
|
|
<child2 name="fred">More text</child2>
|
|
</parent>""", 1)
|
|
\end{verbatim}
|
|
|
|
The output from this program is:
|
|
|
|
\begin{verbatim}
|
|
Start element: parent {'id': 'top'}
|
|
Start element: child1 {'name': 'paul'}
|
|
Character data: 'Text goes here'
|
|
End element: child1
|
|
Character data: '\n'
|
|
Start element: child2 {'name': 'fred'}
|
|
Character data: 'More text'
|
|
End element: child2
|
|
Character data: '\n'
|
|
End element: parent
|
|
\end{verbatim}
|
|
|
|
|
|
\subsection{Content Model Descriptions \label{expat-content-models}}
|
|
\sectionauthor{Fred L. Drake, Jr.}{fdrake@acm.org}
|
|
|
|
Content modules are described using nested tuples. Each tuple
|
|
contains four values: the type, the quantifier, the name, and a tuple
|
|
of children. Children are simply additional content module
|
|
descriptions.
|
|
|
|
The values of the first two fields are constants defined in the
|
|
\code{model} object of the \module{xml.parsers.expat} module. These
|
|
constants can be collected in two groups: the model type group and the
|
|
quantifier group.
|
|
|
|
The constants in the model type group are:
|
|
|
|
\begin{datadescni}{XML_CTYPE_ANY}
|
|
The element named by the model name was declared to have a content
|
|
model of \code{ANY}.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CTYPE_CHOICE}
|
|
The named element allows a choice from a number of options; this is
|
|
used for content models such as \code{(A | B | C)}.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CTYPE_EMPTY}
|
|
Elements which are declared to be \code{EMPTY} have this model type.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CTYPE_MIXED}
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CTYPE_NAME}
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CTYPE_SEQ}
|
|
Models which represent a series of models which follow one after the
|
|
other are indicated with this model type. This is used for models
|
|
such as \code{(A, B, C)}.
|
|
\end{datadescni}
|
|
|
|
|
|
The constants in the quantifier group are:
|
|
|
|
\begin{datadescni}{XML_CQUANT_NONE}
|
|
No modifier is given, so it can appear exactly once, as for \code{A}.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CQUANT_OPT}
|
|
The model is optional: it can appear once or not at all, as for
|
|
\code{A?}.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CQUANT_PLUS}
|
|
The model must occur one or more times (like \code{A+}).
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_CQUANT_REP}
|
|
The model must occur zero or more times, as for \code{A*}.
|
|
\end{datadescni}
|
|
|
|
|
|
\subsection{Expat error constants \label{expat-errors}}
|
|
|
|
The following constants are provided in the \code{errors} object of
|
|
the \refmodule{xml.parsers.expat} module. These constants are useful
|
|
in interpreting some of the attributes of the \exception{ExpatError}
|
|
exception objects raised when an error has occurred.
|
|
|
|
The \code{errors} object has the following attributes:
|
|
|
|
\begin{datadescni}{XML_ERROR_ASYNC_ENTITY}
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF}
|
|
An entity reference in an attribute value referred to an external
|
|
entity instead of an internal entity.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_BAD_CHAR_REF}
|
|
A character reference referred to a character which is illegal in XML
|
|
(for example, character \code{0}, or `\code{\&\#0;}'.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_BINARY_ENTITY_REF}
|
|
An entity reference referred to an entity which was declared with a
|
|
notation, so cannot be parsed.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_DUPLICATE_ATTRIBUTE}
|
|
An attribute was used more than once in a start tag.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_INCORRECT_ENCODING}
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_INVALID_TOKEN}
|
|
Raised when an input byte could not properly be assigned to a
|
|
character; for example, a NUL byte (value \code{0}) in a UTF-8 input
|
|
stream.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_JUNK_AFTER_DOC_ELEMENT}
|
|
Something other than whitespace occurred after the document element.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_MISPLACED_XML_PI}
|
|
An XML declaration was found somewhere other than the start of the
|
|
input data.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_NO_ELEMENTS}
|
|
The document contains no elements (XML requires all documents to
|
|
contain exactly one top-level element)..
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_NO_MEMORY}
|
|
Expat was not able to allocate memory internally.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_PARAM_ENTITY_REF}
|
|
A parameter entity reference was found where it was not allowed.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_PARTIAL_CHAR}
|
|
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_RECURSIVE_ENTITY_REF}
|
|
An entity reference contained another reference to the same entity;
|
|
possibly via a different name, and possibly indirectly.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_SYNTAX}
|
|
Some unspecified syntax error was encountered.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_TAG_MISMATCH}
|
|
An end tag did not match the innermost open start tag.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_UNCLOSED_TOKEN}
|
|
Some token (such as a start tag) was not closed before the end of the
|
|
stream or the next token was encountered.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_UNDEFINED_ENTITY}
|
|
A reference was made to a entity which was not defined.
|
|
\end{datadescni}
|
|
|
|
\begin{datadescni}{XML_ERROR_UNKNOWN_ENCODING}
|
|
The document encoding is not supported by Expat.
|
|
\end{datadescni}
|