1 =head1 NAME

     2 

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

     4 

     5 =head1 DESCRIPTION

     6 

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

     8 

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

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

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

    12 user command like cut or rearranging a document by moving fragments

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

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

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

    16 can potentially be a heavyweight object, depending on the underlying

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

    18 object. DocumentFragment is such an object.

    19 

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

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

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

    23 the child list of this node.

    24 

    25 The children of a DocumentFragment node are zero or more nodes

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

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

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

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

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

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

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

    33 

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

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

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

    37 makes the DocumentFragment very useful when the user wishes to create

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

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

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