asXMLTreeNode: Convert a regular XML node to one for use in a "flat" tree

Description

This coerces a regular R-based XML node (i.e. not an internal C-level node) to a form that can be inserted into a flat tree, i.e. one that stores the nodes in a non-hierarchical manner. It is thus used in conjunction with xmlHashTree and xmlFlatListTree. It adds id and env fields to the node and specializes the class by prefixing className to the class attribute.

This is not used very much anymore as we use the internal nodes for most purposes.

Usage

asXMLTreeNode(node, env, id = get(".nodeIdGenerator", env)(xmlName(node)),
              className = "XMLTreeNode")

Arguments

node

the original XML node

env

the XMLFlatTree object into which this node will be inserted.

the identifier for the node in the flat tree. If this is not specified, we consult the tree itself and its built-in identifier generator. By default, the name of the node is used as its identifier unless there is another node with that name.

className

a vector of class names to be prefixed to the existing class vector of the node.

Value

An object of class className, i.e. by default "XMLTreeNode".

References

http://www.w3.org/XML

Examples

Run this code

# NOT RUN {
  txt = '<foo a="123" b="an attribute"><bar>some text</bar>other text</foo>'
  doc = xmlTreeParse(txt)

  class(xmlRoot(doc))

  as(xmlRoot(doc), "XMLInternalNode")
# }