=head1 NAME

XML::LibXML::Node - "virtual" Base Class DOM-Nodes

=head1 synopsis

 use XML::LibXML

 $name = $node->getName();
 $name = $node->nodeName;
 $node->setName( $newName );
 $bool = $node->isSameNode( $other_node );
 $bool = $node->isEqual( $other_node );
 $content = $node->getData()
 $content = $node->nodeValue;
 $type = $node->getType();
 $type = $node->nodeType;
 $node->unbindNode()
 $childnode = $node->removeChild( $childnode )
 $oldnode = $node->replaceChild( $newNode, $oldNode )
 $node->replaceNode($newNode);
 $childnode = $node->appendChild( $childnode )
 $node->addSibling($newNode);
 $newnode =$node->cloneNode( $deep )
 @attrs =$node->attributes;
 $parentnode = $node->getParentNode();
 $parentnode = $node->parentNode;
 $nextnode = $node->getNextSibling()
 $nextnode = $node->nextSibling()
 $nextnode = $node->getPreviousSibling()
 $prevnode = $node->previousSibling()
 $boolean = $node->hasChildNodes();
 $childnode = $node->getFirstChild()
 $childnode = $node->firstChild;
 $childnode = $node->getLastChild()
 $childnode = $node->lastChild;
 $dom = $node->getOwnerDocument()
 $documentnode = $node->ownerDocument;
 $node = $node->getOwner;
 $node->setOwnerDocument( $dom );
 $node->insertBefore( $newNode, $refNode )
 $node->insertAfter( $newNode, $refNode )
 @nodes = $node->findnodes( $xpath_statement );
 $result = $node->find( $xpath );
 print $node->findvalue( $xpath );
 @children = $node->getChildnodes();
 @childnodes = $node->childNodes;
 $xmlstring = $node->toString();
 $name = $node->getLocalName();
 $localname = $node->localname;
 $name = $node->getPrefix();
 $nameprefix = $node->prefix;
 $uri = $node->getNamespaceURI()
 $boolean = $node->hasAttributes();
 @attributelist = $node->attributesNS( $URI );
 @nslist = $node->getNamespaces();
 $node->iterator( \&nodehandler );
 $node->normalize


=head1 DESCRIPTION


LibXML::Node defines functions that are common to all
Node Types. A LibXML::Node should never be created
standalone, but as an instance of a high level class
such as LibXML::Element or LibXML::Text. The class
itself should provide only common functionality. In
XML::LibXML each node is part either of a document or
a document-fragment. Because of this there is no node
without a parent. This may causes confusion with
"unbound" nodes.


=head2 Methods

=over 4

=item B<getName>


Returns the node's name. This Function is aware
about namesaces and returns the full name of the
current node (I<prefix:localname>)


=item B<nodeName>


Alias for B<getName()>.


=item B<setName>


In very limited situation it is usefull to change
a nodes name. In the DOM specification this should
throw an error. This Function is not aware about
namespaces yet.


=item B<isSameNode>


returns TRUE (1) if the given nodes refer to the same
nodestructure, otherwise FALSE (0) is returned.


=item B<isEqual>


depraced version of isSameNode().
B<NOTE> isEqual will change behaviour to follow the DOM specification

=item B<getData>


If the node has any content (such as stored in a
I<text node>) it can get requested through
this function.


=item B<nodeValue>


Alias for B<getData>


=item B<getType>


Retrun the node's type. The possible types are
described in the libxml2 B<tree.h>
documentation. The return value of this function
is a numeric value. Therefore it differst with the
result of perl ref function.


=item B<nodeType>


Alias for B<getType>.


=item B<unbindNode>


Unbinds the Node from its siblings and Parent, but
not from the Document it belongs to. If the node
is not inserted into the DOM afterwards it will be
lost after the programm terminated. From a low
level view, the unbound node is stripped from the
context it is and inserted into a (hidden)
document-fragment.


=item B<removeChild>


This will unbind the Child Node from its parent
I<$node>. The function returns the unbound
node. If I<oldNode> is not a child of the
given Node the function will fail.


=item B<replaceChild>


Replaces the I<$oldNode> with the
I<$newNode>. The I<$oldNode> will be
unbound from the Node. This function differs from
the DOM L2 specification, in the case, if the new
node is not part of the document, the node will be
imported first.


=item B<replaceNode>


This function is very similar to replaceChild(), but it replaces the node itself rather than a childnode. This is useful if a node found by any XPath function, should be replaced.


=item B<appendChild>


The function will add the I<$childnode> to
the end of I<$node>'s children. The function
should fail, if the new childnode is allready a
child of I<$node>. This function differs
from the DOM L2 specification, in the case, if the
new node is not part of the document, the node
will be imported first.


=item B<addSibling>


addSibling() allows to add an additional node to the end of a nodelist, defined by the given node.


=item B<cloneNode>

B<cloneNode> creates a copy of
I<$node>. Wether $deep is set to 1 (true)
the function will copy all childnodes as well. If
$deep is 0 only the current node will be copied.


=item B<attributes>


This function returns all attributes assigned to the given node. if this function is called in scalar context, it will return a XML::LibXML::NodeList. 

=item B<getParentNode>


Returns simply the Parent Node of the current node. 

=item B<parentNode>


Alias for B<getParentNode()>


=item B<getNextSibling>


Returns the next sibling if any .


=item B<nextSibling>


Alias for B<getNextSibling()>


=item B<getPreviousSibling>


Analogous to B<getNextSibling> the function
returns the previous sibling if any.


=item B<previousSibling>


Alias for B<getPreviousSibling()>


=item B<hasChildNodes>


If the current node has Childnodes this function
returns TRUE (1), otherwise it returns FALSE (0,
not undef).


=item B<getFirstChild>


If a node has childnodes this function will return
the first node in the childlist.


=item B<firstChild>


Alias for B<getFirstChild()>


=item B<getLastChild>


If the I<$node> has childnodes this function
returns the last child node.


=item B<lastChild>


Alias for B<getLastChild()>


=item B<getOwnerDocument>


Through this function it is allways possible to
access the document the current node is bound to.


=item B<ownerDocument>


Alias for B<getOwnerDocument()>


=item B<getOwner>


This function returns the node the current node is
associated with. In the very most cases this will
be a document node or a document fragment node.


=item B<setOwnerDocument>


This function binds a node to another DOM. This
method unbinds the node first, if it is allready
bound to another document.

Note that this is only safe with single nodes but not with subtrees. In case of subtrees one should use XML::LibXML::Document's importNode method.


=item B<insertBefore>


The method inserts I<$newNode> before
I<$refNode>. If I<$refNode> is
undefined, the newNode will be set as the new
first child of the parent node. This function
differs from the DOM L2 specification, in the
case, if the new node is not part of the document,
the node will be imported first.


=item B<insertAfter>


The method inserts I<$newNode> after
I<$refNode>. If I<$refNode> is
undefined, the newNode will be set as the new last
child of the parent node.


=item B<findnodes>

B<findnodes> performs the xpath statement on
the current node and returns the result as an
array. In scalar context returns a
I<XML::LibXML::NodeList> object.


=item B<find>

B<find> performs the xpath expression using
the current node as the context of the expression,
and returns the result depending on what type of
result the XPath expression had. For example, the
XPath "1 * 3 + 52" results in a
I<XML::LibXML::Number> object being
returned. Other expressions might return a
I<XML::LibXML::Boolean> object, or a
I<XML::LibXML::Literal> object (a
string). Each of those objects uses Perl's
overload feature to "do the right thing" in
different contexts.


=item B<findvalue>

B<findvalue> is exactly equivalent to:

 $node->find( $xpath )->to_literal;
                
That is, it returns the literal value of the
results. This enables you to ensure that you get a
string back from your search, allowing certain
shortcuts. This could be used as the equivalent of
<xsl:value-of select="some_xpath"/>.


=item B<getChildnodes>


Alias for B<childNodes()>


=item B<childNodes>

B<getChildnodes> implements a more intuitive
interface to the childnodes of the current
node. It enables you to pass all children directly
to a I<map> or I<grep>. If this
function is called in scalar context, the number
of childnodes will be returned.


=item B<toString>


This is the equivalent to
I<XML::LibXML::Document::toString> for a
single node. This means a node and all its
childnodes will be dumped into the result string.

There is no formating implemented yet, which may
cause an unreadable output.


=item B<getLocalName>


Returns the local name of a tag. This is the part
behind the colon.


=item B<localname>


Alias for B<getLocalName()>


=item B<getPrefix>


Returns the prefix of a tag. This is the part
before the colon.


=item B<prefix>


Alias for B<getPrefix()>


=item B<getNamespaceURI>


returns the URI of the current namespace.


=item B<hasAttributes>


returns 1 (TRUE) if the current node has any
attributes set, otherwise 0 (FALSE) is returned.


=item B<getAttributesNS>


returns all attributes for the given namespace.
(not implemented yet)


=item B<getNamespaces>


returns all the namespace declaration nodes bound
to this node. The items are instances of the class
XML::LibXML::Namespace.


=item B<iterator>


This is little helper function, that lets one
define a function, that will be processed on the
current node and all its children. The function
will recieve as its only parameter the node to
proceed. The function uses inorder proceeding to
traverse the subtree. Therefore you can't reach
the childnodes anymore, if the nodehandler removes
childnodes.

 $node->iterator( sub { print $_[0]->nodeName(),"\n"; } );
                
The example will print all node names in the current subtree.

The B<iterator> function will return the
return value of the nodehandler while processing
the last child of the current node.


=item B<normalize>


This function normalizes adjacent textnodes. This
function is not as strict as libxml2's
xmlTextMerge() function, since it will not free a
node that is still refered by the perl layer.


=back

=head1 AUTHOR

Matt Sergeant, Christian Glahn

=head1 SEE ALSO

XML::LibXML, XML::LibXML::Element, XML::LibXML::Text, XML::LibXML::Comment, XML::LibXML::Attr, XML::LibXML::DocumentFragment

=head1 VERSION

1.49

