XML::TreeBuilder(3pm) | User Contributed Perl Documentation | XML::TreeBuilder(3pm) |
XML::TreeBuilder - Parser that builds a tree of XML::Element objects
foreach my $file_name (@ARGV) { my $tree = XML::TreeBuilder->new({ 'NoExpand' => 0, 'ErrorContext' => 0 }); # empty tree $tree->parse_file($file_name); print "Hey, here's a dump of the parse tree of $file_name:\n"; $tree->dump; # a method we inherit from XML::Element print "And here it is, bizarrely rerendered as XML:\n", $tree->as_XML, "\n"; # Now that we're done with it, we must destroy it. $tree = $tree->delete; }
This module uses XML::Parser to make XML document trees constructed of XML::Element objects (and XML::Element is a subclass of HTML::Element adapted for XML). XML::TreeBuilder is meant particularly for people who are used to the HTML::TreeBuilder / HTML::Element interface to document trees, and who don't want to learn some other document interface like XML::Twig or XML::DOM.
The way to use this class is to:
1. start a new (empty) XML::TreeBuilder object.
2. set any of the "store" options you want.
3. then parse the document from a source by calling "$x->parsefile(...)" or "$x->parse(...)" (See XML::Parser docs for the options that these two methods take)
4. do whatever you need to do with the syntax tree, presumably involving traversing it looking for some bit of information in it,
5. and finally, when you're done with the tree, call $tree->delete to erase the contents of the tree from memory. This kind of thing usually isn't necessary with most Perl objects, but it's necessary for TreeBuilder objects. See HTML::Element for a more verbose explanation of why this is the case.
XML::TreeBuilder is a subclass of XML::Element, which in turn is a subclass of HTML:Element. You should read and understand the documentation for those two modules.
An XML::TreeBuilder object is just a special XML::Element object that allows you to call these additional methods:
Parameters:
Passed to XML::Parser. Do not Expand external entities. Default: undef
Passed to XML::Parser. Number of context lines to generate on errors. Default: undef
Path to an Oasis XML catalog. Passed to XML::Catalog to resolve entities if NoExpand is not set. Default: $ENV{XML_CATALOG_FILES} || '/etc/xml/catalog'
Currently, this is off (false) by default.
XML::Parser, XML::Element, HTML::TreeBuilder, HTML::DOMbo.
And for alternate XML document interfaces, XML::DOM and XML::Twig.
Copyright (c) 2000,2004 Sean M. Burke. All rights reserved. Copyright (c) 2010,2011,2013 Jeff Fearn. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.
Current Author: Jeff Fearn <jfearn@cpan.org>.
Former Authors: Sean M. Burke, <sburke@cpan.org>
2022-06-28 | perl v5.34.0 |