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Daniel Veillard8f40f1e2002-08-28 21:18:45 +0000[diff] [blame]19<a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo"></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo"></a><a href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo"></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo"></a></div>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]20</td>
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22<h1>The XML C library for Gnome</h1>
23<h2>Python and bindings</h2>
24</td></tr></table></td></tr></table></td>
25</tr></table>
26<table border="0" cellpadding="4" cellspacing="0" width="100%" align="center"><tr><td bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="2" width="100%"><tr>
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Daniel Veillardfc59c092002-06-05 14:48:26 +0000[diff] [blame]58<li><a href="tutorial/index.html">Tutorial</a></li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]59<li>
60<a href="xml.html">flat page</a>, <a href="site.xsl">stylesheet</a>
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62</ul></td></tr>
63</table>
64<table width="100%" border="0" cellspacing="1" cellpadding="3">
65<tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>API Indexes</b></center></td></tr>
Daniel Veillard5ede35e2002-10-01 11:37:35 +0000[diff] [blame]66<tr><td bgcolor="#fffacd">
Daniel Veillard595978c2002-10-09 18:46:35 +0000[diff] [blame]67<form action="search.php" enctype="application/x-www-form-urlencoded" method="GET">
Daniel Veillard5ede35e2002-10-01 11:37:35 +0000[diff] [blame]68<input name="query" type="TEXT" size="20" value=""><input name="submit" type="submit" value="Search ...">
69</form>
70<ul>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]71<li><a href="APIchunk0.html">Alphabetic</a></li>
72<li><a href="APIconstructors.html">Constructors</a></li>
73<li><a href="APIfunctions.html">Functions/Types</a></li>
74<li><a href="APIfiles.html">Modules</a></li>
75<li><a href="APIsymbols.html">Symbols</a></li>
Daniel Veillard5ede35e2002-10-01 11:37:35 +0000[diff] [blame]76</ul>
77</td></tr>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]78</table>
79<table width="100%" border="0" cellspacing="1" cellpadding="3">
80<tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Related links</b></center></td></tr>
81<tr><td bgcolor="#fffacd"><ul>
82<li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li>
83<li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li>
84<li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]85<li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]86<li><a href="ftp://xmlsoft.org/">FTP</a></li>
87<li><a href="http://www.fh-frankfurt.de/~igor/projects/libxml/">Windows binaries</a></li>
88<li><a href="http://garypennington.net/libxml2/">Solaris binaries</a></li>
Daniel Veillardcb7543b2002-09-09 10:54:06 +0000[diff] [blame]89<li><a href="http://www.zveno.com/open_source/libxml2xslt.html">MacOsX binaries</a></li>
Daniel Veillarde6d8e202002-05-02 06:11:10 +0000[diff] [blame]90<li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li>
Daniel Veillard2d347fa2002-03-17 10:34:11 +0000[diff] [blame]91<li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml&amp;product=libxml2">Bug Tracker</a></li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]92</ul></td></tr>
93</table>
94</td></tr></table></td>
95<td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd">
Daniel Veillard42766c02002-08-22 20:52:17 +0000[diff] [blame]96<p>There are a number of language bindings and wrappers available for
97libxml2, the list below is not exhaustive. Please contact the <a href="http://mail.gnome.org/mailman/listinfo/xml-bindings">xml-bindings@gnome.org</a>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]98(<a href="http://mail.gnome.org/archives/xml-bindings/">archives</a>) in
99order to get updates to this list or to discuss the specific topic of libxml2
100or libxslt wrappers or bindings:</p>
101<ul>
102<li>
Daniel Veillardc14401e2002-11-20 14:28:17 +0000[diff] [blame]103<a href="http://libxmlplusplus.sourceforge.net/">Libxml++</a> seems the
104 most up-to-date C++ bindings for libxml2, check the <a href="http://libxmlplusplus.sourceforge.net/reference/html/hierarchy.html">documentation</a>
105 and the <a href="http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/libxmlplusplus/libxml%2b%2b/examples/">examples</a>.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]106 <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper
107 based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
108 <li>and a third C++ wrapper by Peter Jones &lt;pjones@pmade.org&gt;
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]109 <p>Website: <a href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a>
110</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]111 </li>
112 <li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]113<a href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]114 Sergeant</a> developed <a href="http://axkit.org/download/">XML::LibXSLT</a>, a Perl wrapper for
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]115 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]116 application server</a>.</li>
117 <li>
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]118<a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]119 earlier version of the libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
120 <li>Gopal.V and Peter Minten develop <a href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
121 C# libxml2 bindings.</li>
122 <li>Petr Kozelka provides <a href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
123 libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
124 <li>Uwe Fechner also provides <a href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
125 implementation for Kylix2/D5/D6 from Borland.</li>
126 <li>Wai-Sun &quot;Squidster&quot; Chia provides <a href="http://www.rubycolor.org/arc/redist/">bindings for Ruby</a> and
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]127 libxml2 bindings are also available in Ruby through the <a href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
128 maintained by Tobias Peters.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]129 <li>Steve Ball and contributors maintains <a href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
130 Tcl</a>.</li>
131 <li>There is support for libxml2 in the DOM module of PHP.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]132</ul>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]133<p>The distribution includes a set of Python bindings, which are guaranteed
134to be maintained as part of the library in the future, though the Python
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]135interface have not yet reached the maturity of the C API.</p>
Daniel Veillard7ef0fcb2002-12-14 10:38:55 +0000[diff] [blame^]136<p>Note to people interested in building bindings, the API is formalized as
137<a href="libxml2-api.xml">an XML API description file</a> which allows to
138automate a large part of the Python bindings, this includes function
139descriptions, enums, structures, typedefs, etc... The Python script used
140to build the bindings is python/generator.py in the source distribution.</p>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]141<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]142<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]143<li>If you use an RPM based distribution, simply install the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxml2-python">libxml2-python
144 RPM</a> (and if needed the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
145 RPM</a>).</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]146 <li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]147 module distribution</a> corresponding to your installed version of
148 libxml2 and libxslt. Note that to install it you will need both libxml2
149 and libxslt installed and run &quot;python setup.py build install&quot; in the
150 module tree.</li>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]151</ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]152<p>The distribution includes a set of examples and regression tests for the
153python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]154excerpts from those tests:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]155<h3>tst.py:</h3>
156<p>This is a basic test of the file interface and DOM navigation:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]157<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]158
159doc = libxml2.parseFile(&quot;tst.xml&quot;)
160if doc.name != &quot;tst.xml&quot;:
161 print &quot;doc.name failed&quot;
162 sys.exit(1)
163root = doc.children
164if root.name != &quot;doc&quot;:
165 print &quot;root.name failed&quot;
166 sys.exit(1)
167child = root.children
168if child.name != &quot;foo&quot;:
169 print &quot;child.name failed&quot;
170 sys.exit(1)
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]171doc.freeDoc()</pre>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]172<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]173xmlParseFile (most of the bindings are automatically generated, and the xml
174prefix is removed and the casing convention are kept). All node seen at the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]175binding level share the same subset of accessors:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]176<ul>
177<li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]178<code>name</code> : returns the node name</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]179 <li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]180<code>type</code> : returns a string indicating the node type</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]181 <li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]182<code>content</code> : returns the content of the node, it is based on
183 xmlNodeGetContent() and hence is recursive.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]184 <li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]185<code>parent</code> , <code>children</code>, <code>last</code>,
186 <code>next</code>, <code>prev</code>, <code>doc</code>,
187 <code>properties</code>: pointing to the associated element in the tree,
188 those may return None in case no such link exists.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]189</ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]190<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]191Reference counting for libxml2 trees would need quite a lot of work to
192function properly, and rather than risk memory leaks if not implemented
193correctly it sounds safer to have an explicit function to free a tree. The
194wrapper python objects like doc, root or child are them automatically garbage
195collected.</p>
196<h3>validate.py:</h3>
197<p>This test check the validation interfaces and redirection of error
198messages:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]199<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]200
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]201#deactivate error messages from the validation
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]202def noerr(ctx, str):
203 pass
204
205libxml2.registerErrorHandler(noerr, None)
206
207ctxt = libxml2.createFileParserCtxt(&quot;invalid.xml&quot;)
208ctxt.validate(1)
209ctxt.parseDocument()
210doc = ctxt.doc()
211valid = ctxt.isValid()
212doc.freeDoc()
213if valid != 0:
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]214 print &quot;validity check failed&quot;</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]215<p>The first thing to notice is the call to registerErrorHandler(), it
216defines a new error handler global to the library. It is used to avoid seeing
217the error messages when trying to validate the invalid document.</p>
218<p>The main interest of that test is the creation of a parser context with
219createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]220parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]221are also available using context methods.</p>
222<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
223C function interfaces in terms of objects method as much as possible. The
224best to get a complete view of what methods are supported is to look at the
225libxml2.py module containing all the wrappers.</p>
226<h3>push.py:</h3>
227<p>This test show how to activate the push parser interface:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]228<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]229
230ctxt = libxml2.createPushParser(None, &quot;&lt;foo&quot;, 4, &quot;test.xml&quot;)
231ctxt.parseChunk(&quot;/&gt;&quot;, 2, 1)
232doc = ctxt.doc()
233
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]234doc.freeDoc()</pre>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]235<p>The context is created with a special call based on the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]236xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]237SAX callback object, then the initial set of data, the length and the name of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]238the resource in case URI-References need to be computed by the parser.</p>
239<p>Then the data are pushed using the parseChunk() method, the last call
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]240setting the third argument terminate to 1.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]241<h3>pushSAX.py:</h3>
242<p>this test show the use of the event based parsing interfaces. In this case
243the parser does not build a document, but provides callback information as
244the parser makes progresses analyzing the data being provided:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]245<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]246log = &quot;&quot;
247
248class callback:
249 def startDocument(self):
250 global log
251 log = log + &quot;startDocument:&quot;
252
253 def endDocument(self):
254 global log
255 log = log + &quot;endDocument:&quot;
256
257 def startElement(self, tag, attrs):
258 global log
259 log = log + &quot;startElement %s %s:&quot; % (tag, attrs)
260
261 def endElement(self, tag):
262 global log
263 log = log + &quot;endElement %s:&quot; % (tag)
264
265 def characters(self, data):
266 global log
267 log = log + &quot;characters: %s:&quot; % (data)
268
269 def warning(self, msg):
270 global log
271 log = log + &quot;warning: %s:&quot; % (msg)
272
273 def error(self, msg):
274 global log
275 log = log + &quot;error: %s:&quot; % (msg)
276
277 def fatalError(self, msg):
278 global log
279 log = log + &quot;fatalError: %s:&quot; % (msg)
280
281handler = callback()
282
283ctxt = libxml2.createPushParser(handler, &quot;&lt;foo&quot;, 4, &quot;test.xml&quot;)
284chunk = &quot; url='tst'&gt;b&quot;
285ctxt.parseChunk(chunk, len(chunk), 0)
286chunk = &quot;ar&lt;/foo&gt;&quot;
287ctxt.parseChunk(chunk, len(chunk), 1)
288
Daniel Veillardfcbfa2d2002-02-21 17:54:27 +0000[diff] [blame]289reference = &quot;startDocument:startElement foo {'url': 'tst'}:&quot; + \
290 &quot;characters: bar:endElement foo:endDocument:&quot;
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]291if log != reference:
292 print &quot;Error got: %s&quot; % log
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]293 print &quot;Expected: %s&quot; % reference</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]294<p>The key object in that test is the handler, it provides a number of entry
295points which can be called by the parser as it makes progresses to indicate
296the information set obtained. The full set of callback is larger than what
297the callback class in that specific example implements (see the SAX
298definition for a complete list). The wrapper will only call those supplied by
299the object when activated. The startElement receives the names of the element
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]300and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]301<p>Also note that the reference string generated from the callback shows a
302single character call even though the string &quot;bar&quot; is passed to the parser
303from 2 different call to parseChunk()</p>
304<h3>xpath.py:</h3>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]305<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]306<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]307
308doc = libxml2.parseFile(&quot;tst.xml&quot;)
309ctxt = doc.xpathNewContext()
310res = ctxt.xpathEval(&quot;//*&quot;)
311if len(res) != 2:
312 print &quot;xpath query: wrong node set size&quot;
313 sys.exit(1)
314if res[0].name != &quot;doc&quot; or res[1].name != &quot;foo&quot;:
315 print &quot;xpath query: wrong node set value&quot;
316 sys.exit(1)
317doc.freeDoc()
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]318ctxt.xpathFreeContext()</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]319<p>This test parses a file, then create an XPath context to evaluate XPath
320expression on it. The xpathEval() method execute an XPath query and returns
321the result mapped in a Python way. String and numbers are natively converted,
322and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]323the document, the XPath context need to be freed explicitly, also not that
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]324the result of the XPath query may point back to the document tree and hence
325the document must be freed after the result of the query is used.</p>
326<h3>xpathext.py:</h3>
327<p>This test shows how to extend the XPath engine with functions written in
328python:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]329<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]330
331def foo(ctx, x):
332 return x + 1
333
334doc = libxml2.parseFile(&quot;tst.xml&quot;)
335ctxt = doc.xpathNewContext()
336libxml2.registerXPathFunction(ctxt._o, &quot;foo&quot;, None, foo)
337res = ctxt.xpathEval(&quot;foo(1)&quot;)
338if res != 2:
339 print &quot;xpath extension failure&quot;
340doc.freeDoc()
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]341ctxt.xpathFreeContext()</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]342<p>Note how the extension function is registered with the context (but that
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]343part is not yet finalized, this may change slightly in the future).</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]344<h3>tstxpath.py:</h3>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]345<p>This test is similar to the previous one but shows how the extension
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]346function can access the XPath evaluation context:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]347<pre>def foo(ctx, x):
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]348 global called
349
350 #
351 # test that access to the XPath evaluation contexts
352 #
353 pctxt = libxml2.xpathParserContext(_obj=ctx)
354 ctxt = pctxt.context()
355 called = ctxt.function()
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]356 return x + 1</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]357<p>All the interfaces around the XPath parser(or rather evaluation) context
358are not finalized, but it should be sufficient to do contextual work at the
359evaluation point.</p>
360<h3>Memory debugging:</h3>
361<p>last but not least, all tests starts with the following prologue:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]362<pre>#memory debug specific
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]363libxml2.debugMemory(1)</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]364<p>and ends with the following epilogue:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]365<pre>#memory debug specific
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]366libxml2.cleanupParser()
367if libxml2.debugMemory(1) == 0:
368 print &quot;OK&quot;
369else:
370 print &quot;Memory leak %d bytes&quot; % (libxml2.debugMemory(1))
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]371 libxml2.dumpMemory()</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]372<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]373allocated block in the library are tracked. The prologue then cleans up the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]374library state and checks that all allocated memory has been freed. If not it
375calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p>
376<p><a href="bugs.html">Daniel Veillard</a></p>
377</td></tr></table></td></tr></table></td></tr></table></td>
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