This is a constructor for the Doctype class that can be provided at the top of an XML document to provide information about the class of document, i.e. its DTD or schema. Also, there is a method for converting such a Doctype
object to a character string.
Doctype(system = character(), public = character(), name ="")
Arguments
system: the system URI that locates the DTD.
public: the identifier for locating the DTD in a catalog, for example. This should be a character vector of length 2, giving the public identifier and a URI. If just the public identifier is given and a string is given for system argument, the system value is used as the second element of public. The public identifer should be of the form +//creator//name//language
where the first element is either + or -, and the language is described by a code in the ISO 639 document.
name: the name of the root element in the document. This should be the first parameter, but is left this way for backward compatability. And
d = Doctype(name ="section", public = c("-//OASIS//DTD DocBook XML V4.2//EN","http://oasis-open.org/docbook/xml/4.2/docbookx.dtd")) as(d,"character")# this call switches the system to the URI associated with the PUBLIC element. d = Doctype(name ="section", public = c("-//OASIS//DTD DocBook XML V4.2//EN"), system ="http://oasis-open.org/docbook/xml/4.2/docbookx.dtd")