XML (version 3.98-1.2)

parseDTD: Read a Document Type Definition (DTD)

Description

Represents the contents of a DTD as a user-level object containing the element and entity definitions.

Usage

parseDTD(extId, asText=FALSE, name="", isURL=FALSE, error = xmlErrorCumulator())

Arguments

extId

The name of the file containing the DTD to be processed.

asText

logical indicating whether the value of `extId' is the name of a file or the DTD content itself. Use this when the DTD is read as a character vector, before being parsed and handed to the parser as content only.

name

Optional name to provide to the parsing mechanism.

isURL

A logical value indicating whether the input source is to be considred a URL or a regular file or string containing the XML.

error

an R function that is called when an error is encountered. This can report it and continue or terminate by raising an error in R. See the error parameter for link{xmlTreeParse}.

Value

• A list with two entries, one for the entities and the other for the elements defined within the DTD.
• entities
  a named list of the entities defined in the DTD. Each entry is indexed by the name of the corresponding entity. Each is an object of class XMLEntity or alternatively XMLExternalEntity if the entity refers to an external definition. The fields of these types of objects are

  • name

  {the name of the entity by which users refer to it.} content{the expanded value or definition of the entity} original{the value of the entity, but with references to other entities not expanded, but maintained in symbolic form.}

item

• elements
• type
• contents
• attributes
• name
• type
• defaultType
• defaultValue

code

XMLAttributeDef

itemize

• name

WARNING

Errors in the DTD are stored as warnings for programmatic access.

Details

Parses and converts the contents of the DTD in the specified file into a user-level object containing all the information about the DTD.

References

http://www.w3.org

See Also

xmlTreeParse, WritingXML.html in the distribution.

Examples

dtdFile <- system.file("exampleData", "foo.dtd",package="XML")
 parseDTD(dtdFile)

txt <- readLines(dtdFile)
txt <- paste(txt,  collapse="")
d <- parseDTD(txt, asText=TRUE)


url <- "http://www.omegahat.org/XML/DTDs/DatasetByRecord.dtd"
 d <- parseDTD(url, asText=FALSE)