The result of installing the package is a an executable program, Sxslt. This is an extension of the Xalan program developed by the Apache Software Foundation. Essentially, it allows one to call arbitrary S functions from within XSL templates and expressions. One can generate output within S and include in the resulting XML document. Additionally, one can use S functions in if, choose, etc. conditionals. This is well-suited to dynamic report generation, publication of reproducible research papers, etc.

The command line arguments for Sxslt are the same as that for the standard Xalan program testXSLT, currently with one extension, --R. Therefore, all of the usual commands are available. For a detailed list, see http://xml.apache.org/xalan-c/commandline.html and you can also invoke Sxslt with no arguments. (As the set of supported flags and options changes in the Apache distribution, we will attempt to track them.)

I should point out two things:

• "This product includes software developed by the Apache Software Foundation (http://www.apache.org/)."
• The ease with which this package was created and the small amount of code is an indication of how well the Xalan code has been designed. It is a remarkably flexible piece of software that has been built to be extended. Congratulations to its authors.