;;; Hey, emacs, this file is -*- Mode: common-lisp; -*- ... got that?

(in-package :lkb)

;;;
;;; determine surface order of constituents in rule: returns list of paths into
;;; feature structure of rule, i.e. (nil (args first) (args rest first)) for a
;;; binary rule, where the first list element is the path to the mother node of
;;; the rule.
;;;

(defun establish-linear-precedence (rule)
  (let ((daughters
         (loop
             for args = (existing-dag-at-end-of rule '(ARGS))
             then (existing-dag-at-end-of args *list-tail*)
             for daughter = (when args 
                              (get-value-at-end-of args *list-head*))
             for path = (list 'ARGS) then (append path *list-tail*)
             while (and daughter (not (eq daughter 'no-way-through)))
             collect (append path *list-head*))))
    (if (null daughters)
      (cerror "Ignore it" "Rule without daughters")
      (cons nil daughters))))


(defun spelling-change-rule-p (rule)
  (declare (ignore rule))
  nil)

;;;
;;; create feature structure representation of orthography value for insertion
;;; into the output structure of inflectional rules.
;;;
(defun make-orth-tdfs (orthography)
  (let* ((unification
          (make-unification :lhs (create-path-from-feature-list *orth-path*)
                            :rhs (make-u-value :type orthography)))
         (indef (process-unifications (list unification))))
    (when indef
      (make-tdfs :indef (create-wffs indef)))))