Update of /cvsroot/perl-xml/XML-LibXML-XPathContext
In directory sc8-pr-cvs1:/tmp/cvs-serv24187
Modified Files:
XPathContext.pm
Log Message:
Mention node locking and add examples to POD documentation
Index: XPathContext.pm
===================================================================
RCS file: /cvsroot/perl-xml/XML-LibXML-XPathContext/XPathContext.pm,v
retrieving revision 1.7
retrieving revision 1.8
diff -u -d -r1.7 -r1.8
--- XPathContext.pm 20 Mar 2003 14:51:45 -0000 1.7
+++ XPathContext.pm 25 Mar 2003 21:05:33 -0000 1.8
@@ -114,7 +114,7 @@
$xc->registerNs($prefix, $namespace_uri);
$xc->registerFunction($name, sub { ... });
$xc->registerFunctionNS($name, $namespace_uri, sub { ... });
- $xc->registerVariableLookup(sub { ... },$data);
+ $xc->registerVariableLookup(sub { ... }, $data);
my @nodes = $xc->findnodes($xpath);
my $nodelist = $xc->findnodes($xpath);
@@ -129,9 +129,60 @@
This module augments XML::LibXML by providing Perl interface to
libxml2's xmlXPathContext structure. Besides just performing xpath
statements on XML::LibXML's node trees it allows redefining certaint
-aspects of xpath engine.
+aspects of XPath engine. This modules allows
-=head2 Methods
+=over 4
+
+=item 1
+
+registering namespace prefixes,
+
+=item 2
+
+defining XPath functions in Perl,
+
+=item 3
+
+defining variable lookup functions in Perl.
+
+=back
+
+=head1 EXAMPLES
+
+=head2 Find all paragraph nodes in XHTML document
+
+This example demonstrates I<registerNs()> usage:
+
+ my $xc = XML::LibXML::XPathContext->new($xhtml_doc);
+ $xc->registerNs('xhtml', 'http://www.w3.org/1999/xhtml');
+ my @nodes = $xc->findnodes('//xhtml:p');
+
+=head2 Find all nodes which names match a Perl regular expression
+
+This example demonstrates I<registerFunction()> usage:
+
+ my $perlmatch = sub {
+ die "Not a nodelist"
+ unless $_[0]->isa('XML::LibXML::NodeList');
+ die "Missing a regular expression"
+ unless defined $_[1];
+
+ my $nodelist = XML::LibXML::NodeList->new;
+
+ my $i = 0;
+ while(my $node = $_[0]->get_node($i)) {
+ $nodelist->push($node) if $node->nodeName =~ $_[1];
+ $i ++;
+ }
+
+ return $nodelist;
+ };
+
+ my $xc = XML::LibXML::XPathContext->new($node);
+ $xc->registerFunction('perlmatch', $perlmatch);
+ my @nodes = $xc->findnodes('perlmatch(//*, "foo|bar")');
+
+=head1 METHODS
=over 4
@@ -211,15 +262,27 @@
=back
+=head1 BUGS AND CAVEATS
+
+L<XML::LibXML::XPathContext> objects are not reentrant. It means you
+cannot register a Perl function with a L<XML::LibXML::XPathContext>
+object if this Perl function uses itself same
+L<XML::LibXML::XPathContext> object internally.
+
+For example following code will not work:
+
+ my $xc = XML::LibXML::XPathContext->new($node);
+ $xc->registerFunction('func', sub { $xc->findvalue('1') });
+ my $result = $xc->findvalue('func()');
+
=head1 AUTHORS
-Based on L<XML::LibXML> code by Matt Sergeant and Christian Glahn.
+Based on L<XML::LibXML> and L<XML::XSLT> code by Matt Sergeant and
+Christian Glahn.
Maintained by Ilya Martynov and Petr Pajas.
-Copyright 2001-2002 AxKit.com Ltd, All rights reserved.
-
-Copyright 2003 Ilya Martynov, All rights reserved.
+Copyright 2001-2003 AxKit.com Ltd, All rights reserved.
=head1 SUPPORT
|
