Facilities for working with XML strings

These functions and classes are used to represent and parse a string whose content is known to be XML. xml allows us to mark a character vector as containing XML, i.e. of class XMLString.

xmlParseString is a convenience routine for converting an XML string into an XML node/tree.

isXMLString is examines a strings content and heuristically determines whether it is XML.

Usage

isXMLString(str)
xmlParseString(content, doc = NULL, namespaces = RXMLNamespaces,
                clean = TRUE, addFinalizer = NA) 
xml(x)

Arguments

str,x,content: the string containing the XML material.
doc: if specified, an XMLInternalDocument object which is used to "house" the new nodes. Specifically, when the nodes are created, they are made as part of this document. This may not be as relevant now with the garbage collection being done at a node and document level. But it still potentially of some value.
namespaces: a character vector giving the URIs for the XML namespaces which are to be removed if clean is TRUE.
clean: a logical value that controls whether namespaces are removed after the document is parsed..
addFinalizer: a logical value or identifier for a C routine that controls whether we register finalizers on the intenal node.

Value

isXMLString returns a logical value.

xmlParseString returns an object of class XMLInternalElementNode.

xml returns an object of class XMLString identifying the text as XML.

Author

Dncan Temple Lang

Examples

 isXMLString("a regular string < 20 characters long")
#> [1] FALSE
 isXMLString("<a><b>c</b></a>")
#> [1] TRUE

 xmlParseString("<a><b>c</b></a>")
#> <a>
#>   <b>c</b>
#> </a> 

  # We can lie!
 isXMLString(xml("foo"))
#> [1] TRUE