The saxon:script element is a top-level element.
It is used to define an implementation
for an extension function that will be used by Saxon. With
other processors, a different implementation of the same function can be selected,
using mechanisms defined by that processor (for example, xalan:script).
The attributes for saxon:script are the same as the attributes
of the xsl:script element defined in the (now withdrawn) XSLT 1.1
working draft.
The language attribute is mandatory, and must take the value "java".
The values "javascript", "ecmascript", or a QName are also permitted, but in this
case Saxon ignores the saxon:script element.
The implements-prefix attribute is mandatory, its value must be a namespace
prefix that maps to the same namespace URI as the prefix used in the extension function
call.
The src attribute is mandatory for language="java", its value must take the
form "java:fully.qualified.class.Name", for example "java:java.util.Date". It defines
the class containing the implementation of extension functions that use this prefix.
The archive attribute is optional, its value is a space-separated list of URLs
of folders or JAR files that will be searched to find the named class. If the attribute
is omitted, the class is sought on the classpath.
