=head1 NAME

XML::DOM::DocumentFragment - Facilitates cut & paste in XML::DOM documents

=head1 DESCRIPTION

XML::DOM::DocumentFragment extends L<XML::DOM::Node>

DocumentFragment is a "lightweight" or "minimal" Document object. It is

very common to want to be able to extract a portion of a document's

tree or to create a new fragment of a document. Imagine implementing a

user command like cut or rearranging a document by moving fragments

around. It is desirable to have an object which can hold such fragments

and it is quite natural to use a Node for this purpose. While it is

true that a Document object could fulfil this role, a Document object

can potentially be a heavyweight object, depending on the underlying

implementation. What is really needed for this is a very lightweight

object. DocumentFragment is such an object.

Furthermore, various operations -- such as inserting nodes as children

of another Node -- may take DocumentFragment objects as arguments; this

results in all the child nodes of the DocumentFragment being moved to

the child list of this node.

The children of a DocumentFragment node are zero or more nodes

representing the tops of any sub-trees defining the structure of the

document. DocumentFragment nodes do not need to be well-formed XML

documents (although they do need to follow the rules imposed upon

well-formed XML parsed entities, which can have multiple top nodes).

For example, a DocumentFragment might have only one child and that

child node could be a Text node. Such a structure model represents

neither an HTML document nor a well-formed XML document.

When a DocumentFragment is inserted into a Document (or indeed any

other Node that may take children) the children of the DocumentFragment

and not the DocumentFragment itself are inserted into the Node. This

makes the DocumentFragment very useful when the user wishes to create

nodes that are siblings; the DocumentFragment acts as the parent of

these nodes so that the user can use the standard methods from the Node

interface, such as insertBefore() and appendChild().