``
is encountered. If an opening tag requires a corresponding closing tag, like
```` ... ``
``, the class should define the :meth:`start_tag` method; if
a tag requires no closing tag, like ````, the class should define the
:meth:`do_tag` method.
The module defines a parser class and an exception:
.. class:: HTMLParser(formatter)
This is the basic HTML parser class. It supports all entity names required by
the XHTML 1.0 Recommendation (https://www.w3.org/TR/xhtml1). It also defines
handlers for all HTML 2.0 and many HTML 3.0 and 3.2 elements.
.. exception:: HTMLParseError
Exception raised by the :class:`~HTMLParser.HTMLParser` class when it encounters an error
while parsing.
.. versionadded:: 2.4
.. seealso::
Module :mod:`formatter`
Interface definition for transforming an abstract flow of formatting events into
specific output events on writer objects.
Module :mod:`HTMLParser`
Alternate HTML parser that offers a slightly lower-level view of the input, but
is designed to work with XHTML, and does not implement some of the SGML syntax
not used in "HTML as deployed" and which isn't legal for XHTML.
Module :mod:`htmlentitydefs`
Definition of replacement text for XHTML 1.0 entities.
Module :mod:`sgmllib`
Base class for :class:`~HTMLParser.HTMLParser`.
.. _html-parser-objects:
HTMLParser Objects
------------------
In addition to tag methods, the :class:`~HTMLParser.HTMLParser` class provides some
additional methods and instance variables for use within tag methods.
.. attribute:: HTMLParser.formatter
This is the formatter instance associated with the parser.
.. attribute:: HTMLParser.nofill
Boolean flag which should be true when whitespace should not be collapsed, or
false when it should be. In general, this should only be true when character
data is to be treated as "preformatted" text, as within a ``
`` element.
The default value is false. This affects the operation of :meth:`handle_data`
and :meth:`save_end`.
.. method:: HTMLParser.anchor_bgn(href, name, type)
This method is called at the start of an anchor region. The arguments
correspond to the attributes of the ```` tag with the same names. The
default implementation maintains a list of hyperlinks (defined by the ``HREF``
attribute for ```` tags) within the document. The list of hyperlinks is
available as the data attribute :attr:`anchorlist`.
.. method:: HTMLParser.anchor_end()
This method is called at the end of an anchor region. The default
implementation adds a textual footnote marker using an index into the list of
hyperlinks created by :meth:`anchor_bgn`.
.. method:: HTMLParser.handle_image(source, alt[, ismap[, align[, width[, height]]]])
This method is called to handle images. The default implementation simply
passes the *alt* value to the :meth:`handle_data` method.
.. method:: HTMLParser.save_bgn()
Begins saving character data in a buffer instead of sending it to the formatter
object. Retrieve the stored data via :meth:`save_end`. Use of the
:meth:`save_bgn` / :meth:`save_end` pair may not be nested.
.. method:: HTMLParser.save_end()
Ends buffering character data and returns all data saved since the preceding
call to :meth:`save_bgn`. If the :attr:`nofill` flag is false, whitespace is
collapsed to single spaces. A call to this method without a preceding call to
:meth:`save_bgn` will raise a :exc:`TypeError` exception.
:mod:`htmlentitydefs` --- Definitions of HTML general entities
==============================================================
.. module:: htmlentitydefs
:synopsis: Definitions of HTML general entities.
.. sectionauthor:: Fred L. Drake, Jr.
.. note::
The :mod:`htmlentitydefs` module has been renamed to :mod:`html.entities` in
Python 3. The :term:`2to3` tool will automatically adapt imports when
converting your sources to Python 3.
**Source code:** :source:`Lib/htmlentitydefs.py`
--------------
This module defines three dictionaries, ``name2codepoint``, ``codepoint2name``,
and ``entitydefs``. ``entitydefs`` is used by the :mod:`htmllib` module to
provide the :attr:`entitydefs` attribute of the :class:`~HTMLParser.HTMLParser` class. The
definition provided here contains all the entities defined by XHTML 1.0 that
can be handled using simple textual substitution in the Latin-1 character set
(ISO-8859-1).
.. data:: entitydefs
A dictionary mapping XHTML 1.0 entity definitions to their replacement text in
ISO Latin-1.
.. data:: name2codepoint
A dictionary that maps HTML entity names to the Unicode code points.
.. versionadded:: 2.3
.. data:: codepoint2name
A dictionary that maps Unicode code points to HTML entity names.
.. versionadded:: 2.3