1. A method for converting a first document to a second document, the method comprising the steps of: specifying the first document in terms of a first extended attribute grammar; specifying the second document in terms of a second extended attribute grammar; specifying an extended attribute coupling grammar of the first and second extended attribute grammars; and transforming the first document into the second document based on the extended attribute coupling grammar.
14. The method of claim 1, wherein the step of specifying the extended attribute coupling grammar comprises the steps of: specifying a first tree sequence of at least one tree of the first document; specifying at least one reduction of the first tree sequence; specifying a second tree sequence of at least one tree of the second document; specifying at least one reduction of the second tree sequence; and specifying at least one reduction operator.