XMLXPathParserContext-class: Class representing the internal data structure for an XSL...

In omegahat/Sxslt: R interface to libxslt

Class representing the internal data structure for an XSL transformation

Description

This class is used to represent the information used by libxslt internally for processing an XSL transformation. In R this is an external pointer that has a reference to the C-level data structure.

Such objects can be used by R functions to find information about the current XSL transformation in effect. Such objects become invalid when the processing is complete and so should not be stored by a function that is passed such an object.

The only way to legitimately obtain such an object is by an XSL operation invoking an R function which is of class XSLTContextFunction, i.e. has that name within its class vector attribute. This is an indication to the R-XSL engine that the context is to be passed as the first argument in the call to such a function.

From this general data structure, we can fetch the input XML document, the top-level XSL style sheet and the output XML document being created with the functions xsltGetInputDocument, xsltGetStyleSheet, xsltGetOutputDocument respectively. There are also convenient as methods to fetch this information via coercion via the as function.

We can use this to fetch the current value of one or more XSL top-level parameters via getXSLVariables.

We can alse use this object to find the point of insertion in the output document and add directly to that from R.

Objects from the Class

A virtual Class: No objects may be created from it.

Extends

Class "oldClass", directly.

Methods

coerce

signature(from = "XMLXPathParserContext", to = "XSLStyleSheet"): get the top-level XSL style sheet associated with this transformation.

coerce

signature(from = "XMLXPathParserContext", to = "XMLInternalDocument"): get the input XML document being transformed by this XSL processing.

Author(s)

Duncan Temple Lang

References

~put references to the literature/web site here ~

See Also

registerXSLFunction

Examples

 showClass("XMLXPathParserContext")

omegahat/Sxslt documentation built on Jan. 17, 2024, 6:44 p.m.