[basex-talk] Pathname of the current XQuery?

I have the awful feeling that I'm missing something really obvious, but I want to be able to get the pathname of the current query, and I can't figure out how.

The use case is that the query validates documents in the collection differently, based on the document element, and I want to refer to the different schema files (which sit, on the file system, right next to the file with the query in it) in a machine-independent way.

So instead of

let $decisionSchema := '/home/graydon/workspace/Content Standards/schemas/decisions_schema.xsd'

I'd like to be able to say something like

let $decisionSchema := concat(string-join(tokenize(get-query-path(),'/')[position() ne last()],'/'),'/decisions_schema.xsd')

only I can't figure out what get-query-path() is.

Thanks! Graydon