;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; 
;;; SYNTACTIC THEORY by Sag and Wasow -- Textbook Grammar 
;;; implementation by Chris Callison-Burch & Scott Guffey
;;;
;;; binding.tdl
;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

#|
IMPLEMENTAION NOTES:
The arg_real-principle rules are an implementation of the textbook's
Argument Realization Principle which states that the argument structure
is the concatenation of the SPR + COMPS, and that items from the COMPS
list on a lexical item may be moved into the GAP list.

The ana_agr-principle rules are an implementation of the binding theory.
Principle A states that "An [ANA +] synsem-struc must be out ranked by
a coindexed synsem-struc" and B that "An [ANA -] synsem-struc must not 
be."  The Anaphoric Agreement Principle states that coindexed elements
share the same AGR value.

Our implementation of the binding theory, relys on the fact
that the parser assigns seperate indicies to elements, unless they are 
explicitly coindexed.  That for covers most of Princple B, but it allows
sentences like "I like me" (which may speakers find acceptable, and 
arguably should be allowed), but counter-indexes "I" and "me".


The version of the GAP correctly moves items according to the book's 
description, but does not do so nearly as concisly.  The rule proliferation
is caused by the fact that there is no clean way to create the "-" operator
in our system.  The major drawback of having so many GAP rules is that they
render the parse charts virtually unreadable.  Previous implementations of
this involved a single binary branching head-complement rule coupled with
a non-branching GAP rule that moved an item from the COMPS to the GAP. 
This was discarded in the interest of producing non-binary branching trees.
|#


;; Can/should we put the case constraint inside these rules?
arg_real-principle-spr-NE := word+arg_real &
[ SYN #syn,
  SEM #sem,
  ARG-ST < #spr . #comps >,

  ARGS < word & [ SYN #syn & [ SPR < #spr >,
			       COMPS #comps,
			       GAP <! !>],
		  SEM #sem,
		  ARG-ST < #spr . #comps > ] > ].


arg_real-principle-spr-empty := word+arg_real &
[ SYN #syn,
  SEM #sem,
  ARG-ST #comps,

  ARGS < word & [ SYN #syn & [ SPR <  >,
			       COMPS #comps,
			       GAP <! !>],
		  SEM #sem,
		  ARG-ST #comps] > ].


#|
;;; I'm leaving this as an example of how to leave the GAP list can be left
;;; too general.  I'm currently limiting extraction to topcial elements.
;;; This helps with parsing speed, makes generated senetences sensible.
;;; CCB
;;;
arg_real-principle-GAP1 :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS #rest,
	GAP <! #1 !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1 . #rest >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].



arg_real-principle-GAP2 :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS < #1 >,
	GAP <! #2 !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1, #2 >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].

arg_real-principle-GAP2b :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS < #1, #3 >,
	GAP <! #2 !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1, #2, #3 >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].


arg_real-principle-GAP3 :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS < #1, #2 >,
	GAP <! #3 !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1, #2, #3 >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].
;;;;
|#



; I'm commenting the gap rules out temporarily to avoid problems
; while debugging the grammar.  SMG

;;;;;

arg_real-principle-GAP1 :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS #rest,
	GAP <! #1 & [SYN [HEAD topic]] !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1 . #rest >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].



arg_real-principle-GAP2 :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS < #1 >,
	GAP <! #2 & [SYN [HEAD topic]] !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1, #2 >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].

arg_real-principle-GAP2b :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS < #1, #3 >,
	GAP <! #2 & [SYN [HEAD topic]] !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD topic & #head,
				  SPR #spr,
				  COMPS < #1, #2, #3 >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].


arg_real-principle-GAP3 :=  word+arg_real &
[ SYN [ HEAD #head,
        SPR #spr,  
	COMPS < #1, #2 >,
	GAP <! #3 & [SYN [HEAD topic]] !> ],
  SEM #sem,
  ARG-ST #arg-st,

  ARGS < word+arg_real & [ SYN [  HEAD #head,
				  SPR #spr,
				  COMPS < #1, #2, #3 >,
				  GAP <! !> ],
			   SEM #sem,
			   ARG-ST #arg-st] > ].
;;;;;



; Beginning of the binding rules...
#|
ana_agr-principle-e := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].


ana_agr-principle-x := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [ ] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].



ana_agr-principle-x+ := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [SYN [HEAD [AGR #agr]],
		      SEM [INDEX #ind]],  [SYN [HEAD [ANA true,
						      AGR #agr]],
					   SEM [INDEX #ind]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].



ana_agr-principle-x- := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [ ],  [SYN [HEAD [ANA false]]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].



ana_agr-principle-x-+ := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [SYN [HEAD [AGR #agr]],
		      SEM [INDEX #ind]], 

		     [SYN [HEAD [ANA false]]],

		     [SYN [HEAD [ANA true,
				 AGR #agr]],
		      SEM [INDEX #ind]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].



ana_agr-principle-x+- := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [SYN [HEAD [AGR #agr]],
		      SEM [INDEX #ind]],      

                     [SYN [HEAD [ ANA true,
			          AGR #agr]],
		      SEM [INDEX #ind]],
		     
		     [SYN [HEAD [ANA false]]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].




ana_agr-principle-x-- := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [ ],  [SYN [HEAD [ANA false]]],
		     [SYN [HEAD [ANA false]]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].



ana_agr-principle-xi+ := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [ ],  [SYN [HEAD [ANA false,
				       AGR #agr]],
			    SEM [INDEX #ind]],       [SYN [HEAD [ANA true,
								 AGR #agr]],
						      SEM [INDEX #ind]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].


ana_agr-principle-x++ := word+arg_real+ana_agr &
[ SYN #syn,
  SEM #sem,
  ARG-ST #arg-st & < [SYN [HEAD [AGR #agr]],
		      SEM [INDEX #ind]],      [SYN [HEAD [ANA true,
							   AGR #agr]],
					       SEM [INDEX #ind]],

		     [SYN [HEAD [ANA true,
				 AGR #agr]],
		      SEM [INDEX #ind]] >,

  ARGS < word+arg_real & [ SYN #syn,
			   SEM #sem,
			   ARG-ST #arg-st ] > ].
|#