<?xml version="1.0"?>
<!DOCTYPE example PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd">
<example><title>A DSSSL Function</title><programlisting>
(define (node-list-filter-by-gi nodelist gilist)
  ;; Returns the node-list that contains every element of the original
  ;; nodelist whose gi is in gilist
  (let loop ((result (empty-node-list)) (nl nodelist))
    (if (node-list-empty? nl)
	result
	(if (member (gi (node-list-first nl)) gilist)
	    (loop (node-list result (node-list-first nl)) 
		  (node-list-rest nl))
	    (loop result (node-list-rest nl))))))
</programlisting></example>
