> Given the map of the document complex types:

Your map isn't complete as it misses out all the elemsnts that are being
tested (SCN, COURCE etc, which makes it hard to help)  a small cut down
well formed example would be easier.

I guess the current node is Student and it has SCN and Instance children



(SCN) (: tests existence of SCN child :)
and
 Instance[COURSEID = ../../Course[contains('HIJCPQRS', substring(COURSEAIM, 1,
1))]/COURSEID]/
   ((: There is an instance with COURSEID equal to the COURSEID of a COURSE
with a COURSEAIM starting with  one of 'HIJCPQRS':)
  EntryProfile[UCASAPPID]/DOMICILE[.='XH']"
  which (the Course element) has a  EntryProfile that has a UCASAPPID
and an DOMICILE with value 'XH'


>  How do we know which of the students Instances to use for checking
> the COURSEID and for the EntryProfile.DOMICILE?
they are all checked and the overall test is true if any one of them
has the right form.

David

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