I used the Grammar Matrix information structure library to produce a Russian grammar fragment with free word order (which is not officially supported), and am currently trying to make it so it it covers all the basic sentences that I have which include intransitive, transitive, ditransitive, and sentences with clausal complements and embedded questions.
The library produces phrase structure rules which constrain the verb’s arguments’ ICONS-KEY for focus or topic (depending on what the user said in the questionnaire with respect to whether focus is clause-final or whatever). They also have ``periphery’’ constraints which are there to prevent multiple parses. They basically look like this:
head-periph-subj-phrase := decl-head-subj-phrase & head-initial-head-nexus & [ NON-HEAD-DTR.SYNSEM [ R-PERIPH +, LOCAL.CONT.HOOK.ICONS-KEY semantic-focus ], SYNSEM [ R-PERIPH +, L-PERIPH + ], HEAD-DTR.SYNSEM [ R-PERIPH -, L-PERIPH +, LOCAL [ CAT.VAL.COMPS < >, CONT.HOOK.ICONS-KEY contrast-or-topic ] ] ].
The rule above assumes that it is the final one to apply and that the head complement rule had already applied.
My questions are:
(1) What is the meaning of the clause’s own ICONS-KEY?
This is what I get (it is coming from basic-non-rel-clause, I think), and with that in place, I cannot immediately use the clause as a clausal complement, since the head-complement rule wants ICONS-KEY of type topic or focus. I could probably add something like that to the clause type but would that be meaningful?
(2) Additionally, what should happen to the periphery constraints? Would it make sense to have a special head-complement rule for complementizers which ignores them? (I seem to be needing such a rule anyway as free word order does not apply to adpositions).
(3) What about the ICONS diff list? It seems to be empty everywhere. Shouldn’t stuff be put on it and percolate up the tree? How to access the information structure information once the clause has been formed?