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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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53<li><a href="upgrade.html">Upgrading 1.x code</a></li>
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56<li><a href="example.html">A real example</a></li>
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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 Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]103<a href="mailto:ari@lusis.org">Ari Johnson</a> provides a C++ wrapper
104 for libxml:<br>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]105 Website: <a href="http://lusis.org/~ari/xml%2B%2B/">http://lusis.org/~ari/xml++/</a><br>
106 Download: <a href="http://lusis.org/~ari/xml%2B%2B/libxml%2B%2B.tar.gz">http://lusis.org/~ari/xml++/libxml++.tar.gz</a>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]107</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]108 <li>There is another <a href="http://libgdome-cpp.berlios.de/">C++ wrapper
109 based on the gdome2 bindings</a> maintained by Tobias Peters.</li>
110 <li>and a third C++ wrapper by Peter Jones &lt;pjones@pmade.org&gt;
Daniel Veillard9b6fd302002-05-13 12:06:47 +0000[diff] [blame]111 <p>Website: <a href="http://pmade.org/pjones/software/xmlwrapp/">http://pmade.org/pjones/software/xmlwrapp/</a>
112</p>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]113 </li>
114 <li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]115<a href="http://mail.gnome.org/archives/xml/2001-March/msg00014.html">Matt
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]116 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]117 libxml2/libxslt as part of the <a href="http://axkit.com/">AxKit XML
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]118 application server</a>.</li>
119 <li>
Daniel Veillard21473672002-06-17 07:29:22 +0000[diff] [blame]120<a href="mailto:dkuhlman@cutter.rexx.com">Dave Kuhlman</a> provides an
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]121 earlier version of the libxml/libxslt <a href="http://www.rexx.com/~dkuhlman">wrappers for Python</a>.</li>
122 <li>Gopal.V and Peter Minten develop <a href="http://savannah.gnu.org/projects/libxmlsharp">libxml#</a>, a set of
123 C# libxml2 bindings.</li>
124 <li>Petr Kozelka provides <a href="http://sourceforge.net/projects/libxml2-pas">Pascal units to glue
125 libxml2</a> with Kylix, Delphi and other Pascal compilers.</li>
126 <li>Uwe Fechner also provides <a href="http://sourceforge.net/projects/idom2-pas/">idom2</a>, a DOM2
127 implementation for Kylix2/D5/D6 from Borland.</li>
128 <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]129 libxml2 bindings are also available in Ruby through the <a href="http://libgdome-ruby.berlios.de/">libgdome-ruby</a> module
130 maintained by Tobias Peters.</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]131 <li>Steve Ball and contributors maintains <a href="http://tclxml.sourceforge.net/">libxml2 and libxslt bindings for
132 Tcl</a>.</li>
133 <li>There is support for libxml2 in the DOM module of PHP.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]134</ul>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]135<p>The distribution includes a set of Python bindings, which are guaranteed
136to be maintained as part of the library in the future, though the Python
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]137interface have not yet reached the maturity of the C API.</p>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]138<p>To install the Python bindings there are 2 options:</p>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]139<ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]140<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
141 RPM</a> (and if needed the <a href="http://rpmfind.net/linux/rpm2html/search.php?query=libxslt-python">libxslt-python
142 RPM</a>).</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]143 <li>Otherwise use the <a href="ftp://xmlsoft.org/python/">libxml2-python
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]144 module distribution</a> corresponding to your installed version of
145 libxml2 and libxslt. Note that to install it you will need both libxml2
146 and libxslt installed and run &quot;python setup.py build install&quot; in the
147 module tree.</li>
Daniel Veillard0b79dfe2002-02-23 13:02:31 +0000[diff] [blame]148</ul>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]149<p>The distribution includes a set of examples and regression tests for the
150python bindings in the <code>python/tests</code> directory. Here are some
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]151excerpts from those tests:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]152<h3>tst.py:</h3>
153<p>This is a basic test of the file interface and DOM navigation:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]154<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]155
156doc = libxml2.parseFile(&quot;tst.xml&quot;)
157if doc.name != &quot;tst.xml&quot;:
158 print &quot;doc.name failed&quot;
159 sys.exit(1)
160root = doc.children
161if root.name != &quot;doc&quot;:
162 print &quot;root.name failed&quot;
163 sys.exit(1)
164child = root.children
165if child.name != &quot;foo&quot;:
166 print &quot;child.name failed&quot;
167 sys.exit(1)
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]168doc.freeDoc()</pre>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]169<p>The Python module is called libxml2; parseFile is the equivalent of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]170xmlParseFile (most of the bindings are automatically generated, and the xml
171prefix is removed and the casing convention are kept). All node seen at the
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]172binding level share the same subset of accessors:</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]173<ul>
174<li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]175<code>name</code> : returns the node name</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]176 <li>
Daniel Veillardc0801af2002-05-28 16:28:42 +0000[diff] [blame]177<code>type</code> : returns a string indicating the node type</li>
Daniel Veillard0b28e882002-07-24 23:47:05 +0000[diff] [blame]178 <li>
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]179<code>content</code> : returns the content of the node, it is based on
180 xmlNodeGetContent() and hence is recursive.</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>parent</code> , <code>children</code>, <code>last</code>,
183 <code>next</code>, <code>prev</code>, <code>doc</code>,
184 <code>properties</code>: pointing to the associated element in the tree,
185 those may return None in case no such link exists.</li>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]186</ul>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]187<p>Also note the need to explicitly deallocate documents with freeDoc() .
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]188Reference counting for libxml2 trees would need quite a lot of work to
189function properly, and rather than risk memory leaks if not implemented
190correctly it sounds safer to have an explicit function to free a tree. The
191wrapper python objects like doc, root or child are them automatically garbage
192collected.</p>
193<h3>validate.py:</h3>
194<p>This test check the validation interfaces and redirection of error
195messages:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]196<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]197
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]198#deactivate error messages from the validation
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]199def noerr(ctx, str):
200 pass
201
202libxml2.registerErrorHandler(noerr, None)
203
204ctxt = libxml2.createFileParserCtxt(&quot;invalid.xml&quot;)
205ctxt.validate(1)
206ctxt.parseDocument()
207doc = ctxt.doc()
208valid = ctxt.isValid()
209doc.freeDoc()
210if valid != 0:
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]211 print &quot;validity check failed&quot;</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]212<p>The first thing to notice is the call to registerErrorHandler(), it
213defines a new error handler global to the library. It is used to avoid seeing
214the error messages when trying to validate the invalid document.</p>
215<p>The main interest of that test is the creation of a parser context with
216createFileParserCtxt() and how the behaviour can be changed before calling
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]217parseDocument() . Similarly the informations resulting from the parsing phase
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]218are also available using context methods.</p>
219<p>Contexts like nodes are defined as class and the libxml2 wrappers maps the
220C function interfaces in terms of objects method as much as possible. The
221best to get a complete view of what methods are supported is to look at the
222libxml2.py module containing all the wrappers.</p>
223<h3>push.py:</h3>
224<p>This test show how to activate the push parser interface:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]225<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]226
227ctxt = libxml2.createPushParser(None, &quot;&lt;foo&quot;, 4, &quot;test.xml&quot;)
228ctxt.parseChunk(&quot;/&gt;&quot;, 2, 1)
229doc = ctxt.doc()
230
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]231doc.freeDoc()</pre>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]232<p>The context is created with a special call based on the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]233xmlCreatePushParser() from the C library. The first argument is an optional
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]234SAX callback object, then the initial set of data, the length and the name of
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]235the resource in case URI-References need to be computed by the parser.</p>
236<p>Then the data are pushed using the parseChunk() method, the last call
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]237setting the third argument terminate to 1.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]238<h3>pushSAX.py:</h3>
239<p>this test show the use of the event based parsing interfaces. In this case
240the parser does not build a document, but provides callback information as
241the parser makes progresses analyzing the data being provided:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]242<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]243log = &quot;&quot;
244
245class callback:
246 def startDocument(self):
247 global log
248 log = log + &quot;startDocument:&quot;
249
250 def endDocument(self):
251 global log
252 log = log + &quot;endDocument:&quot;
253
254 def startElement(self, tag, attrs):
255 global log
256 log = log + &quot;startElement %s %s:&quot; % (tag, attrs)
257
258 def endElement(self, tag):
259 global log
260 log = log + &quot;endElement %s:&quot; % (tag)
261
262 def characters(self, data):
263 global log
264 log = log + &quot;characters: %s:&quot; % (data)
265
266 def warning(self, msg):
267 global log
268 log = log + &quot;warning: %s:&quot; % (msg)
269
270 def error(self, msg):
271 global log
272 log = log + &quot;error: %s:&quot; % (msg)
273
274 def fatalError(self, msg):
275 global log
276 log = log + &quot;fatalError: %s:&quot; % (msg)
277
278handler = callback()
279
280ctxt = libxml2.createPushParser(handler, &quot;&lt;foo&quot;, 4, &quot;test.xml&quot;)
281chunk = &quot; url='tst'&gt;b&quot;
282ctxt.parseChunk(chunk, len(chunk), 0)
283chunk = &quot;ar&lt;/foo&gt;&quot;
284ctxt.parseChunk(chunk, len(chunk), 1)
285
Daniel Veillardfcbfa2d2002-02-21 17:54:27 +0000[diff] [blame]286reference = &quot;startDocument:startElement foo {'url': 'tst'}:&quot; + \
287 &quot;characters: bar:endElement foo:endDocument:&quot;
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]288if log != reference:
289 print &quot;Error got: %s&quot; % log
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]290 print &quot;Expected: %s&quot; % reference</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]291<p>The key object in that test is the handler, it provides a number of entry
292points which can be called by the parser as it makes progresses to indicate
293the information set obtained. The full set of callback is larger than what
294the callback class in that specific example implements (see the SAX
295definition for a complete list). The wrapper will only call those supplied by
296the object when activated. The startElement receives the names of the element
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]297and a dictionary containing the attributes carried by this element.</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]298<p>Also note that the reference string generated from the callback shows a
299single character call even though the string &quot;bar&quot; is passed to the parser
300from 2 different call to parseChunk()</p>
301<h3>xpath.py:</h3>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]302<p>This is a basic test of XPath wrappers support</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]303<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]304
305doc = libxml2.parseFile(&quot;tst.xml&quot;)
306ctxt = doc.xpathNewContext()
307res = ctxt.xpathEval(&quot;//*&quot;)
308if len(res) != 2:
309 print &quot;xpath query: wrong node set size&quot;
310 sys.exit(1)
311if res[0].name != &quot;doc&quot; or res[1].name != &quot;foo&quot;:
312 print &quot;xpath query: wrong node set value&quot;
313 sys.exit(1)
314doc.freeDoc()
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]315ctxt.xpathFreeContext()</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]316<p>This test parses a file, then create an XPath context to evaluate XPath
317expression on it. The xpathEval() method execute an XPath query and returns
318the result mapped in a Python way. String and numbers are natively converted,
319and node sets are returned as a tuple of libxml2 Python nodes wrappers. Like
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]320the document, the XPath context need to be freed explicitly, also not that
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]321the result of the XPath query may point back to the document tree and hence
322the document must be freed after the result of the query is used.</p>
323<h3>xpathext.py:</h3>
324<p>This test shows how to extend the XPath engine with functions written in
325python:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]326<pre>import libxml2
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]327
328def foo(ctx, x):
329 return x + 1
330
331doc = libxml2.parseFile(&quot;tst.xml&quot;)
332ctxt = doc.xpathNewContext()
333libxml2.registerXPathFunction(ctxt._o, &quot;foo&quot;, None, foo)
334res = ctxt.xpathEval(&quot;foo(1)&quot;)
335if res != 2:
336 print &quot;xpath extension failure&quot;
337doc.freeDoc()
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]338ctxt.xpathFreeContext()</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]339<p>Note how the extension function is registered with the context (but that
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]340part is not yet finalized, this may change slightly in the future).</p>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]341<h3>tstxpath.py:</h3>
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]342<p>This test is similar to the previous one but shows how the extension
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]343function can access the XPath evaluation context:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]344<pre>def foo(ctx, x):
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]345 global called
346
347 #
348 # test that access to the XPath evaluation contexts
349 #
350 pctxt = libxml2.xpathParserContext(_obj=ctx)
351 ctxt = pctxt.context()
352 called = ctxt.function()
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]353 return x + 1</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]354<p>All the interfaces around the XPath parser(or rather evaluation) context
355are not finalized, but it should be sufficient to do contextual work at the
356evaluation point.</p>
357<h3>Memory debugging:</h3>
358<p>last but not least, all tests starts with the following prologue:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]359<pre>#memory debug specific
Daniel Veillardaf43f632002-03-08 15:05:20 +0000[diff] [blame]360libxml2.debugMemory(1)</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]361<p>and ends with the following epilogue:</p>
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]362<pre>#memory debug specific
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]363libxml2.cleanupParser()
364if libxml2.debugMemory(1) == 0:
365 print &quot;OK&quot;
366else:
367 print &quot;Memory leak %d bytes&quot; % (libxml2.debugMemory(1))
Daniel Veillard9eb146b2002-02-21 16:04:51 +0000[diff] [blame]368 libxml2.dumpMemory()</pre>
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]369<p>Those activate the memory debugging interface of libxml2 where all
Daniel Veillard63d83142002-05-20 06:51:05 +0000[diff] [blame]370allocated block in the library are tracked. The prologue then cleans up the
Daniel Veillard6dbcaf82002-02-20 14:37:47 +0000[diff] [blame]371library state and checks that all allocated memory has been freed. If not it
372calls dumpMemory() which saves that list in a <code>.memdump</code> file.</p>
373<p><a href="bugs.html">Daniel Veillard</a></p>
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