XML (version 1.7-2)

newXMLDoc: Create internal XML node or document object

Description

These are used to create internal `libxml' nodes and top-level document objects that are used to write XML trees. While the functions are available, their direct use is not encouraged. Instead, use xmlTree as the functions need to be used within a strict regime to avoid corrupting C level structures.

Usage

newXMLDoc(dtd, namespaces=NULL)
newXMLNode(name, ..., attrs = NULL, namespace="", doc=NULL, .children = list(...))
newXMLTextNode(text, doc = NULL)
newXMLCDataNode(text, doc = NULL)
newXMLCommentNode(text, doc = NULL)
newXMLPINode(name,  text, doc = NULL)
newXMLDTDNode(nodeName, externalID = character(), systemID = character(), doc = NULL)

Arguments

dtd

the name of the DTD to use for the XML document.

namespaces

a named character vector with each element specifying a name space identifier and the corresponding URI for that namespace that are to be declared and used in the XML document, \ e.g. c(shelp = "http://www.omegahat.org/XML/SHelp")

name

the tag/element name for the XML node and the for a Processing Instruction (PI) node, this is the "target", e.g. the identifier for the system for whose attention this PI node is intended.

...

the children of this node. These can be other nodes created earlier or R strings that are converted to text nodes and added as children to this newly created node.

attrs

a named list of name-value pairs to be used as attributes for the XML node.

namespace

the short or alias for the namespace to use for this XML node

doc

the XMLInternalDocument object created with newXMLDoc that is used to root the node.

.children

a list containing XML node elements or content. This is an alternative form of specifying the child nodes than ...which is useful for programmatic interaction when the "sub"-content is already in a list rather than a loose collection of values.

text

the text content for the new XML node

nodeName

the name of the node to put in the DOCTYPE element that will appear as the top-most node in the XML document.

externalID

the PUBLIC identifier for the document type. This is a string of the form A//B//C//D. A is either + or -; B identifies the person or insitution that defined the format (i.e. the "creator"); C is the name of the format; and language is

systemID

the SYSTEM identifier for the DTD for the document. This is a URI

Value

• Each function returns an R object that points to the C-level structure instance. These are of class XMLInternalDocument and XMLInternalNode, respectively

Details

These create internal C level objects/structure instances that can be added to a libxml DOM and subsequently inserted into other document objects or ``serialized'' to textual form.

References

http://www.w3.org/XML, http://www.xmlsoft.org, http://www.omegahat.org

See Also

xmlTree saveXML

Examples

x = summary(rnorm(1000))
d = xmlTree()
d$addNode("table", close = FALSE)

d$addNode("tr", .children = sapply(names(x), function(x) d$addNode("th", x)))
d$addNode("tr", .children = sapply(x, function(x) d$addNode("td", format(x))))

d$closeNode()


# Just doctype
z = xmlTree("people", dtd = "people")
# no public element
z = xmlTree("people", dtd = c("people", "", "http://www.omegahat.org/XML/types.dtd"))
# public and system
z = xmlTree("people", dtd = c("people", "//a//b//c//d", "http://www.omegahat.org/XML/types.dtd"))

# Using a DTD node directly.
dtd = newXMLDTDNode(c("people", "", "http://www.omegahat.org/XML/types.dtd"))
z = xmlTree("people", dtd = dtd)


x = rnorm(3)
z = xmlTree("r:data", namespaces = c(r = "http://www.r-project.org"))
z$addNode("numeric", attrs = c("r:length" = length(x)), close = FALSE)
lapply(x, function(v) z$addNode("el", x))
z$closeNode()
# should give   <r:data><numeric r:length="3"/></r:data>


# shows namespace prefix on an attribute, and different from the one on the node.
z = xmlTree()
z$addNode("r:data",  namespace = c(r = "http://www.r-project.org", omg = "http://www.omegahat.org"), close = FALSE)
x = rnorm(3)
z$addNode("r:numeric", attrs = c("omg:length" = length(x)))



z = xmlTree("people", namespaces = list(r = "http://www.r-project.org"))
z$setNamespace("r")

z$addNode("person", attrs = c(id = "123"), close = FALSE)
z$addNode("firstname", "Duncan")
z$addNode("surname", "Temple Lang")
z$addNode("title", "Associate Professor")
z$addNode("expertize", close = FALSE)
z$addNode("topic", "Data Technologies")
z$addNode("topic", "Programming Language Design")
z$addNode("topic", "Parallel Computing")
z$addNode("topic", "Data Visualization")
z$closeTag()
z$addNode("address", "4210 Mathematical Sciences Building, UC Davis")