;; -*- Mode: Lisp; -*-

;;; Tiny Rule Engine, Version 5

;;; Copyright (c) 1993, Kenneth D. Forbus, Northwestern University,
;;; and Johan de Kleer, the Xerox Corporation.
;;; All rights reserved.

;;; See the file legal.txt for a paragraph stating scope of permission
;;; and disclaimer of warranty.  The above copyright notice and that
;;; paragraph must be included in any separate copy of this file.

(in-package :cl-user)

;; A very simple pattern-directed inference system.
;; This version is the simplest.

(defvar *tre-path* (make-bps-path "tre") "Path for Tiny Rule Engine source files.")

(defvar *tre-files*
  '("tinter" ;; User interface
    "data"   ;; Assertions and database
    "rules"  ;; Storing and retrieving rules
    "unify"  ;; Pattern matching & variables
    "treex1" ;; Examples for tre
    )
  "Tiny Rule Engine source files.")

(defun load-tre (&key (action :compile-if-newer))
   "Load the Tiny Rule Engine"
  (bps-load-files *tre-path* *tre-files* :action action))

(defun shakedown-tre ()
   "Run examples to ensure that tre is working properly."
   (format t "~%Beginning shakedown...~%")
   (ex1)
   (ex2)
   (format t "~%  ... shakedown completed.~%"))

(defun help-tre (&optional (stream *standard-output*))
   "Print out some helpful information about the Tiny Rule Engine."
   (dolist (statement
            '("~%Tiny Rule Engine:"
              "===================================================="
              "  to load:    (load-tre :action :load-source)"
              "  to compile: (load-tre :action :compile)"
              "  Examples to run (see treex1.lsp):"
              "    (ex1 t)  ;; Modus Ponens."
              "    (ex2 t)  ;; Parts inferences."
              "    (ex3 t)  ;; Inductive reasoning of worst sort (careful!)."
              ""
              ))
      (format stream statement) (terpri stream)))

(help-tre)