NAME

XML::TreeBuilder - Parser that builds a tree of XML::Element objects

SYNOPSIS

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;
}

DESCRIPTION

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.

METHODS AND ATTRIBUTES

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:

$root = XML::TreeBuilder->new()

Construct a new XML::TreeBuilder object.

Parameters:

NoExpand

Passed to XML::Parser. Do not Expand external entities.
Default: undef

ErrorContext

Passed to XML::Parser. Number of context lines to generate on errors.
Default: undef

catalog

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'

$root->eof

Deletes parser object.

$root->parse(...options...)

Uses XML::Parser's parse method to parse XML from the source(s?) specified by the options. See XML::Parse

$root->parsefile(...options...)

Uses XML::Parser's parsefile method to parse XML from the source(s?) specified by the options. See XML::Parse

$root->parse_file(...options...)

Simply an alias for parsefile.

$root->store_comments(value)

This determines whether TreeBuilder will normally store comments found while parsing content into $root. Currently, this is off by default.

$root->store_declarations(value)

This determines whether TreeBuilder will normally store markup declarations found while parsing content into $root. Currently, this is off by default.

$root->store_pis(value)

This determines whether TreeBuilder will normally store processing instructions found while parsing content into $root. Currently, this is off (false) by default.

$root->store_cdata(value)

This determines whether TreeBuilder will normally store CDATA sectitons found while parsing content into $root. Adds a ~cdata node.

Currently, this is off (false) by default.

SEE ALSO

XML::Parser, XML::Element, HTML::TreeBuilder, HTML::DOMbo.

And for alternate XML document interfaces, XML::DOM and XML::Twig.

COPYRIGHT AND DISCLAIMERS

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.

AUTHOR

Current Author: Jeff Fearn <jfearn@cpan.org>.

Former Authors: Sean M. Burke, <sburke@cpan.org>