let dbms_of_xml = function
Xml.Element
("li",_,
[Xml.Element("tuple",_,
[
Xml.Element ("ti",_,[db]) ;
Xml.Element ("ti",_,[col]) ;
]
)
]
) ->
let db = db_of_xml db in
let col = coldbms_of_xml col in
(db, col)
| e ->
fail e "dbms_of_xml"