NAME

       XML::XUpdate::LibXML - Simple implementation of XUpdate format

SYNOPSIS

       use XML::LibXML; use XML::XUpdate::LibXML;

       $parser  = XML::LibXML->new(); $dom     = $parser->parse_file("mydoc.xml"); $actions =
       $parser->parse_file("update.xml");

       $xupdate = XML::XUpdate::LibXML->new(); $xupdate->process($dom->getDocumentElement(),
       $actions); print $dom->toString(),"\n";

DESCRIPTION

       This module implements the XUpdate format described in XUpdate Working Draft from
       2000-09-14 (http://www.xmldb.org/xupdate/xupdate-wd.html).  The implementation is based on
       XML::LibXML DOM API.

   "new"
           my $xupdate = XML::XUpdate::LibXML->new();

       Creates a new XUpdate object. You may use this object to update several different DOM
       trees using several different XUpdate descriptions. The advantage of it is that an xupdate
       object remembers values all variables declared in XUpdate documents.

   "$xupdate->registerNs($prefix,$uri)"
       Tell the XPath engine to resolve given namespace prefix as the given namespace URI. This
       is particularly useful to bind a default namespace to a prefix because XPath doesn't
       honour default namespaces.

   "$xupdate->process($document_dom,$xupdate_dom)"
       This function takes two DOM trees as its arguments. It works by updating the first tree
       according to all XUpdate commands included in the second one. All XUpdate commands must be
       children of the root element of the second tree and must all belong to XUpdate namespace
       "http://www.xmldb.org/xupdate". The namespace URI may be changed with set_namespace
       method.

   "$xupdate->set_namespace($URI)"
       You may use this method to change the namespace of XUpdate elements.  The default
       namespace is "http://www.xmldb.org/xupdate".

   "$xupdate->namespace()"
       Returns XUpdate namespace URI used by XUpdate processor to identify XUpdate commands.

   EXPORT
       None.

DIFFERENCES BETWEEN 0.2.x and 0.3.x

       In 0.3.x different implementation of XUpdate variables is used. Now variables contain the
       actual objects resulting from an XPath query, and not their textual content as in versions
       0.2.x of XML::XUpdate::LibXML.

       Also, value-of instruction results in copies of the actual objects it selects rather than
       their textual content as in 0.2.x.

       I hope the new implementation is more conformant with the (not very clear) XUpdate Working
       Draft and therefore more compatible with other XUpdate implementations.

DIFFERENCES BETWEEN 0.3.x and 0.4.x

       Commands are applied to all nodes of the select nodeset, not just the first one.

DIFFERENCES BETWEEN 0.4.x and 0.5.x

       XML::LibXML::XPathContext is used for variable code providing more flexible and powerfull
       implementation. New and hopefully correct implementation of the problematic child
       attribute of update command has been introduced.

       Support for registrering namespace prefix with the XPath engine (allows binding document's
       default namespace to a prefix).

       Several bug fixes.

DIFFERENCES BETWEEN 0.5.x and 0.6.x

       xu:if command implementation contributed by Amir Guindehi.

AUTHOR

       Petr Pajas, pajas@matfyz.cz

COPYRIGHT

       Copyright 2002-2005 Petr Pajas, All rights reserved.

       This program is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.

SEE ALSO

       XML::LibXML XML::LibXML::XPathContext