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