lxml
====

.. meta::
  :description: lxml - the most feature-rich and easy-to-use library for working with XML and HTML in the Python language
  :keywords: lxml, etree, objectify, Python, XML, HTML

.. class:: pagequote

| `» lxml takes all the pain out of XML. « <http://thread.gmane.org/gmane.comp.python.lxml.devel/3252/focus=3258>`_
| Stephan Richter

.. class:: eyecatcher

|   lxml is the most feature-rich
|   and easy-to-use library
|   for working with XML and HTML
|   in the Python language.

.. 
   1  Introduction
   2  Documentation
   3  Download
   4  Mailing list
   5  Bug tracker
   6  License
   7  Old Versions


Introduction
------------

lxml is a Pythonic binding for the libxml2_ and libxslt_ libraries.  It is
unique in that it combines the speed and feature completeness of these
libraries with the simplicity of a native Python API, mostly compatible but
superior to the well-known ElementTree_ API.  See the introduction_ for more
information about background and goals.  Some common questions are answered in
the FAQ_.

.. _libxml2: http://xmlsoft.org
.. _libxslt: http://xmlsoft.org/XSLT

.. _introduction: intro.html
.. _FAQ:          FAQ.html


Documentation
-------------

* ElementTree:

  * `ElementTree API`_

  * compatibility_ and differences of lxml.etree

  * `benchmark results`_

* lxml.etree:

  * the `lxml.etree Tutorial`_

  * `lxml.etree specific API`_ documentation

  * the `generated API documentation`_ as a reference

  * parsing_ and validating_ XML

  * `XPath and XSLT`_ support

  * Python `extension functions`_ for XPath and XSLT

  * `custom element classes`_ for custom XML APIs

  * a `SAX compliant API`_ for interfacing with other XML tools

  * a `C-level API`_ for interfacing with external C/Pyrex modules

* lxml.objectify:

  * `lxml.objectify`_ API documentation

  * a brief comparison of `objectify and etree`_

lxml.etree follows the ElementTree_ API as much as possible, building it on
top of the native libxml2 tree.  If you are new to ElementTree, start with the
`lxml.etree Tutorial`_.  See also the ElementTree compatibility_ overview and
the `benchmark results`_ comparing lxml to the original ElementTree_ and
cElementTree_ implementations.

Right after the `lxml.etree Tutorial`_ and the ElementTree_ documentation, the
most important place to look is the `lxml.etree specific API`_ documentation.
It describes how lxml extends the ElementTree API to expose libxml2 and
libxslt specific functionality, such as XPath_, `Relax NG`_, `XML Schema`_,
`XSLT`_, and `c14n`_.  Python code can be called from XPath expressions and
XSLT stylesheets through the use of `extension functions`_.  lxml also offers
a `SAX compliant API`_, that works with the SAX support in the standard
library.

There is a separate module `lxml.objectify`_ that implements a data-binding
API on top of lxml.etree.  See the `objectify and etree`_ FAQ entry for a
comparison.

In addition to the ElementTree API, lxml also features a sophisticated API for
`custom element classes`_.  This is a simple way to write arbitrary XML driven
APIs on top of lxml.  As of version 1.1, lxml.etree has a new `C-level API`_
that can be used to efficiently extend lxml.etree in external C modules,
including custom element class support.

.. _ElementTree:  http://effbot.org/zone/element-index.htm
.. _`ElementTree API`:  http://effbot.org/zone/element-index.htm#documentation
.. _cElementTree: http://effbot.org/zone/celementtree.htm

.. _`lxml.etree Tutorial`: tutorial.html
.. _`generated API documentation`:   api/index.html
.. _`benchmark results`: performance.html
.. _`compatibility`: compatibility.html
.. _`lxml.etree specific API`: api.html
.. _`parsing`: parsing.html
.. _`validating`: validation.html
.. _`XPath and XSLT`: xpathxslt.html
.. _`extension functions`: extensions.html
.. _`custom element classes`: element_classes.html
.. _`SAX compliant API`: sax.html
.. _`C-level API`: capi.html
.. _`lxml.objectify`: objectify.html
.. _`objectify and etree`: FAQ.html#what-is-the-difference-between-lxml-etree-and-lxml-objectify

.. _XPath: http://www.w3.org/TR/xpath
.. _`Relax NG`: http://www.relaxng.org/
.. _`XML Schema`: http://www.w3.org/XML/Schema
.. _`XSLT`: http://www.w3.org/TR/xslt
.. _`c14n`: http://www.w3.org/TR/xml-c14n


Download
--------

The best way to download lxml is to visit `lxml at the Python Package
Index`_ (PyPI).  It has the source that compiles on various platforms.
The source distribution is signed with `this key`_.  Binary builds for
MS Windows usually become available through PyPI a few days after a
source release.  If you can't wait, consider trying a less recent
version first.

.. _`lxml at the Python Package Index`: http://pypi.python.org/pypi/lxml/
.. _`this key`: pubkey.asc

The latest version is `lxml 2.0.4`_, released 2008-04-13
(`changes for 2.0.4`_).  `Older versions`_ are listed below.

.. _`Older versions`: #old-versions

Please take a look at the `installation instructions`_!

.. _`installation instructions`: installation.html

It's also possible to check out the latest development version of lxml
from svn directly, using a command like this::

  svn co http://codespeak.net/svn/lxml/trunk lxml

You can also `browse it through the web`_.  Please read `how to build lxml
from source`_ first.  The `latest CHANGES`_ of the developer version are also
accessible.  You can check there if a bug you found has been fixed or a
feature you want has been implemented in the latest trunk version.

.. _`how to build lxml from source`: build.html
.. _`browse it through the web`: http://codespeak.net/svn/lxml
.. _`latest CHANGES`: http://codespeak.net/svn/lxml/trunk/CHANGES.txt


Mailing list
------------

Questions? Suggestions? Code to contribute? We have a `mailing list`_.

You can search the archive with Gmane_ or Google_.

.. _`mailing list`: http://codespeak.net/mailman/listinfo/lxml-dev
.. _Gmane: http://blog.gmane.org/gmane.comp.python.lxml.devel
.. _Google: http://www.google.com/webhp?q=site:codespeak.net/mailman/listinfo/lxml-dev%20


Bug tracker
-----------

lxml uses the `launchpad bug tracker`_.  If you are sure you found a bug in
lxml, please file a bug report there.  If you are not sure whether some
unexpected behaviour of lxml is a bug or not, please ask on the `mailing
list`_ first.  Do not forget to search the archive (e.g. with Gmane_)!

.. _`launchpad bug tracker`: https://launchpad.net/lxml


License
-------

The lxml library is shipped under a `BSD license`_. libxml2 and libxslt2
itself are shipped under the `MIT license`_. There should therefore be no
obstacle to using lxml in your codebase.

.. _`BSD license`: http://codespeak.net/svn/lxml/trunk/doc/licenses/BSD.txt
.. _`MIT license`: http://www.opensource.org/licenses/mit-license.html


Old Versions
------------

* `lxml 2.0.3`_, released 2008-03-26 (`changes for 2.0.3`_)

* `lxml 2.0.2`_, released 2008-02-22 (`changes for 2.0.2`_)

* `lxml 2.0.1`_, released 2008-02-13 (`changes for 2.0.1`_)

* `lxml 2.0`_, released 2008-02-01 (`changes for 2.0`_)

* `lxml 1.3.6`_, released 2007-10-29 (`changes for 1.3.6`_)

* `lxml 1.3.5`_, released 2007-10-22 (`changes for 1.3.5`_)

* `lxml 1.3.4`_, released 2007-08-30 (`changes for 1.3.4`_)

* `lxml 1.3.3`_, released 2007-07-26 (`changes for 1.3.3`_)

* `lxml 1.3.2`_, released 2007-07-03 (`changes for 1.3.2`_)

* lxml 1.3.1, released 2007-07-02 (`changes for 1.3.1`_)

* `lxml 1.3`_, released 2007-06-24 (`changes for 1.3`_)

* `lxml 1.2.1`_, released 2007-02-27 (`changes for 1.2.1`_)

* `lxml 1.2`_, released 2007-02-20 (`changes for 1.2`_)

* `lxml 1.1.2`_, released 2006-10-30 (`changes for 1.1.2`_)

* `lxml 1.1.1`_, released 2006-09-21 (`changes for 1.1.1`_)

* `lxml 1.1`_, released 2006-09-13 (`changes for 1.1`_)

* `lxml 1.0.4`_, released 2006-09-09 (`changes for 1.0.4`_)

* `lxml 1.0.3`_, released 2006-08-08 (`changes for 1.0.3`_)

* `lxml 1.0.2`_, released 2006-06-27 (`changes for 1.0.2`_)

* `lxml 1.0.1`_, released 2006-06-09 (`changes for 1.0.1`_)

* `lxml 1.0`_, released 2006-06-01 (`changes for 1.0`_)

* `lxml 0.9.2`_, released 2006-05-10 (`changes for 0.9.2`_)

* `lxml 0.9.1`_, released 2006-03-30 (`changes for 0.9.1`_)

* `lxml 0.9`_,   released 2006-03-20 (`changes for 0.9`_)

* `lxml 0.8`_,   released 2005-11-03 (`changes for 0.8`_)

* `lxml 0.7`_,   released 2005-06-15 (`changes for 0.7`_)

* `lxml 0.6`_,   released 2005-05-14 (`changes for 0.6`_)

* `lxml 0.5.1`_, released 2005-04-09 (`changes for 0.5.1`_)

* `lxml 0.5`_,   released 2005-04-08

.. _`lxml 2.0.4`: lxml-2.0.4.tgz
.. _`lxml 2.0.3`: lxml-2.0.3.tgz
.. _`lxml 2.0.2`: lxml-2.0.2.tgz
.. _`lxml 2.0.1`: lxml-2.0.1.tgz
.. _`lxml 2.0`: lxml-2.0.tgz
.. _`lxml 1.3.6`: lxml-1.3.6.tgz
.. _`lxml 1.3.5`: lxml-1.3.5.tgz
.. _`lxml 1.3.4`: lxml-1.3.4.tgz
.. _`lxml 1.3.3`: lxml-1.3.3.tgz
.. _`lxml 1.3.2`: lxml-1.3.2.tgz
.. _`lxml 1.3`: lxml-1.3.tgz
.. _`lxml 1.2.1`: lxml-1.2.1.tgz
.. _`lxml 1.2`: lxml-1.2.tgz
.. _`lxml 1.1.2`: lxml-1.1.2.tgz
.. _`lxml 1.1.1`: lxml-1.1.1.tgz
.. _`lxml 1.1`: lxml-1.1.tgz
.. _`lxml 1.0.4`: lxml-1.0.4.tgz
.. _`lxml 1.0.3`: lxml-1.0.3.tgz
.. _`lxml 1.0.2`: lxml-1.0.2.tgz
.. _`lxml 1.0.1`: lxml-1.0.1.tgz
.. _`lxml 1.0`: lxml-1.0.tgz
.. _`lxml 0.9.2`: lxml-0.9.2.tgz
.. _`lxml 0.9.1`: lxml-0.9.1.tgz
.. _`lxml 0.9`: lxml-0.9.tgz
.. _`lxml 0.8`: lxml-0.8.tgz
.. _`lxml 0.7`: lxml-0.7.tgz
.. _`lxml 0.6`: lxml-0.6.tgz
.. _`lxml 0.5.1`: lxml-0.5.1.tgz
.. _`lxml 0.5`: lxml-0.5.tgz

.. _`changes for 2.0.4`: changes-2.0.4.html
.. _`changes for 2.0.3`: changes-2.0.3.html
.. _`changes for 2.0.2`: changes-2.0.2.html
.. _`changes for 2.0.1`: changes-2.0.1.html
.. _`changes for 2.0`: changes-2.0.html
.. _`changes for 1.3.6`: changes-1.3.6.html
.. _`changes for 1.3.5`: changes-1.3.5.html
.. _`changes for 1.3.4`: changes-1.3.4.html
.. _`changes for 1.3.3`: changes-1.3.3.html
.. _`changes for 1.3.2`: changes-1.3.2.html
.. _`changes for 1.3.1`: changes-1.3.1.html
.. _`changes for 1.3`: changes-1.3.html
.. _`changes for 1.2.1`: changes-1.2.1.html
.. _`changes for 1.2`: changes-1.2.html
.. _`changes for 1.1.2`: changes-1.1.2.html
.. _`changes for 1.1.1`: changes-1.1.1.html
.. _`changes for 1.1`: changes-1.1.html
.. _`changes for 1.0.4`: changes-1.0.4.html
.. _`changes for 1.0.3`: changes-1.0.3.html
.. _`changes for 1.0.2`: changes-1.0.2.html
.. _`changes for 1.0.1`: changes-1.0.1.html
.. _`changes for 1.0`: changes-1.0.html
.. _`changes for 0.9.2`: changes-0.9.2.html
.. _`changes for 0.9.1`: changes-0.9.1.html
.. _`changes for 0.9`: changes-0.9.html
.. _`changes for 0.8`: changes-0.8.html
.. _`changes for 0.7`: changes-0.7.html
.. _`changes for 0.6`: changes-0.6.html
.. _`changes for 0.5.1`: changes-0.5.1.html
