calist.el

   1 ;;; calist.el --- Condition functions
   2
   3 ;; Copyright (C) 1998 MORIOKA Tomohiko.
   4
   5 ;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
   6 ;; Keywords: condition, alist, tree
   7
   8 ;; This file is part of APEL (A Portable Emacs Library).
   9
  10 ;; This program is free software; you can redistribute it and/or
  11 ;; modify it under the terms of the GNU General Public License as
  12 ;; published by the Free Software Foundation; either version 2, or (at
  13 ;; your option) any later version.
  14
  15 ;; This program is distributed in the hope that it will be useful, but
  16 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18 ;; General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 ;; Boston, MA 02111-1307, USA.
  24
  25 ;;; Code:
  26
  27 (eval-when-compile (require 'cl))
  28
  29 (defvar calist-field-match-method-obarray [nil])
  30
  31 (defun define-calist-field-match-method (field-type function)
  32   "Set field-match-method for FIELD-TYPE to FUNCTION."
  33   (fset (intern (symbol-name field-type) calist-field-match-method-obarray)
  34         function))
  35
  36 (defun calist-default-field-match-method (calist field-type field-value)
  37   (let ((s-field (assoc field-type calist)))
  38     (cond ((null s-field)
  39            (cons (cons field-type field-value) calist)
  40            )
  41           ((eq field-value t)
  42            calist)
  43           ((equal (cdr s-field) field-value)
  44            calist))))
  45
  46 (defsubst calist-field-match-method (field-type)
  47   (condition-case nil
  48       (symbol-function
  49        (intern-soft
  50         (symbol-name field-type) calist-field-match-method-obarray))
  51     (error (symbol-function 'calist-default-field-match-method))
  52     ))
  53
  54 (defsubst calist-field-match (calist field-type field-value)
  55   (funcall (calist-field-match-method field-type)
  56            calist field-type field-value))
  57
  58 (defun ctree-match-calist (rule-tree alist)
  59   "Return matched condition-alist if ALIST matches RULE-TREE."
  60   (if (null rule-tree)
  61       alist
  62     (let ((type (car rule-tree))
  63           (choices (cdr rule-tree))
  64           default)
  65       (catch 'tag
  66         (while choices
  67           (let* ((choice (car choices))
  68                  (choice-value (car choice)))
  69             (if (eq choice-value t)
  70                 (setq default choice)
  71               (let ((ret-alist (calist-field-match alist type (car choice))))
  72                 (if ret-alist
  73                     (throw 'tag
  74                            (if (cdr choice)
  75                                (ctree-match-calist (cdr choice) ret-alist)
  76                              ret-alist))
  77                   ))))
  78           (setq choices (cdr choices)))
  79         (if default
  80             (let ((ret-alist (calist-field-match alist type t)))
  81               (if ret-alist
  82                   (if (cdr default)
  83                       (ctree-match-calist (cdr default) ret-alist)
  84                     ret-alist))))
  85         ))))
  86
  87 (defun ctree-match-calist-partially (rule-tree alist)
  88   "Return matched condition-alist if ALIST matches RULE-TREE."
  89   (if (null rule-tree)
  90       alist
  91     (let ((type (car rule-tree))
  92           (choices (cdr rule-tree))
  93           default)
  94       (catch 'tag
  95         (while choices
  96           (let* ((choice (car choices))
  97                  (choice-value (car choice)))
  98             (if (eq choice-value t)
  99                 (setq default choice)
 100               (let ((ret-alist (calist-field-match alist type (car choice))))
 101                 (if ret-alist
 102                     (throw 'tag
 103                            (if (cdr choice)
 104                                (ctree-match-calist-partially
 105                                 (cdr choice) ret-alist)
 106                              ret-alist))
 107                   ))))
 108           (setq choices (cdr choices)))
 109         (if default
 110             (let ((ret-alist (calist-field-match alist type t)))
 111               (if ret-alist
 112                   (if (cdr default)
 113                       (ctree-match-calist-partially (cdr default) ret-alist)
 114                     ret-alist)))
 115           (calist-field-match alist type t))
 116         ))))
 117
 118 (defun ctree-find-calist (rule-tree alist &optional all)
 119   "Return list of condition-alist which matches ALIST in RULE-TREE.
 120 If optional argument ALL is specified, default rules are not ignored
 121 even if other rules are matched for ALIST."
 122   (if (null rule-tree)
 123       (list alist)
 124     (let ((type (car rule-tree))
 125           (choices (cdr rule-tree))
 126           default dest)
 127       (while choices
 128         (let* ((choice (car choices))
 129                (choice-value (car choice)))
 130           (if (eq choice-value t)
 131               (setq default choice)
 132             (let ((ret-alist (calist-field-match alist type (car choice))))
 133               (if ret-alist
 134                   (if (cdr choice)
 135                       (setq dest
 136                             (append (ctree-find-calist
 137                                      (cdr choice) ret-alist all)
 138                                     dest))
 139                     (setq dest (cons ret-alist dest))
 140                     )))))
 141         (setq choices (cdr choices)))
 142       (or (and (not all) dest)
 143           (if default
 144               (let ((ret-alist (calist-field-match alist type t)))
 145                 (if ret-alist
 146                     (if (cdr default)
 147                         (setq dest
 148                               (append (ctree-find-calist
 149                                        (cdr default) ret-alist all)
 150                                       dest))
 151                       (setq dest (cons ret-alist dest))
 152                       ))))
 153           )
 154       dest)))
 155
 156 (defun calist-to-ctree (calist)
 157   "Convert condition-alist CALIST to condition-tree."
 158   (if calist
 159       (let* ((cell (car calist)))
 160         (cons (car cell)
 161               (list (cons (cdr cell)
 162                           (calist-to-ctree (cdr calist))
 163                           ))))))
 164
 165 (defun ctree-add-calist-strictly (ctree calist)
 166   "Add condition CALIST to condition-tree CTREE without default clause."
 167   (cond ((null calist) ctree)
 168         ((null ctree)
 169          (calist-to-ctree calist)
 170          )
 171         (t
 172          (let* ((type (car ctree))
 173                 (values (cdr ctree))
 174                 (ret (assoc type calist)))
 175            (if ret
 176                (catch 'tag
 177                  (while values
 178                    (let ((cell (car values)))
 179                      (if (equal (car cell)(cdr ret))
 180                          (throw 'tag
 181                                 (setcdr cell
 182                                         (ctree-add-calist-strictly
 183                                          (cdr cell)
 184                                          (delete ret (copy-alist calist)))
 185                                         ))))
 186                    (setq values (cdr values)))
 187                  (setcdr ctree (cons (cons (cdr ret)
 188                                            (calist-to-ctree
 189                                             (delete ret (copy-alist calist))))
 190                                      (cdr ctree)))
 191                  )
 192              (catch 'tag
 193                (while values
 194                  (let ((cell (car values)))
 195                    (setcdr cell
 196                            (ctree-add-calist-strictly (cdr cell) calist))
 197                    )
 198                  (setq values (cdr values))))
 199              )
 200            ctree))))
 201
 202 (defun ctree-add-calist-with-default (ctree calist)
 203   "Add condition CALIST to condition-tree CTREE with default clause."
 204   (cond ((null calist) ctree)
 205         ((null ctree)
 206          (let* ((cell (car calist))
 207                 (type (car cell))
 208                 (value (cdr cell)))
 209            (cons type
 210                  (list '(t)
 211                        (cons value (calist-to-ctree (cdr calist)))))
 212            ))
 213         (t
 214          (let* ((type (car ctree))
 215                 (values (cdr ctree))
 216                 (ret (assoc type calist)))
 217            (if ret
 218                (catch 'tag
 219                  (while values
 220                    (let ((cell (car values)))
 221                      (if (equal (car cell)(cdr ret))
 222                          (throw 'tag
 223                                 (setcdr cell
 224                                         (ctree-add-calist-with-default
 225                                          (cdr cell)
 226                                          (delete ret (copy-alist calist)))
 227                                         ))))
 228                    (setq values (cdr values)))
 229                  (setcdr ctree (list* '(t)
 230                                       (cons (cdr ret)
 231                                             (calist-to-ctree
 232                                              (delete ret (copy-alist calist))))
 233                                       (cdr ctree)))
 234                  )
 235              (catch 'tag
 236                (while values
 237                  (let ((cell (car values)))
 238                    (setcdr cell
 239                            (ctree-add-calist-with-default (cdr cell) calist))
 240                    )
 241                  (setq values (cdr values)))
 242                (let ((elt (cons t (calist-to-ctree calist))))
 243                  (or (member elt (cdr ctree))
 244                      (setcdr ctree (cons elt (cdr ctree)))
 245                      )))
 246              )
 247            ctree))))
 248
 249 (defun ctree-set-calist-strictly (ctree-var calist)
 250   "Set condition CALIST in CTREE-VAR without default clause."
 251   (set ctree-var
 252        (ctree-add-calist-strictly (symbol-value ctree-var) calist)))
 253
 254 (defun ctree-set-calist-with-default (ctree-var calist)
 255   "Set condition CALIST to CTREE-VAR with default clause."
 256   (set ctree-var
 257        (ctree-add-calist-with-default (symbol-value ctree-var) calist)))
 258
 259
 260 ;;; @ end
 261 ;;;
 262
 263 (provide 'calist)
 264
 265 ;;; calist.el ends here