;;; symbols --- 

;; JSCL is free software: you can redistribute it and/or
;; modify it under the terms of the GNU General Public License as
;; published by the Free Software Foundation, either version 3 of the
;; License, or (at your option) any later version.
;;
;; JSCL is distributed in the hope that it will be useful, but
;; WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;; General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with JSCL.  If not, see <http://www.gnu.org/licenses/>.

(defun symbol-plist (x)
  (cond
    ((not (symbolp x))
     (error "`~a' is not a symbol." x))
    ((in "plist" x)
     (oget* x "plist"))))

(defun set-symbol-plist (new-value x)
  (if (symbolp x)
      (oset* new-value x "plist")
      (error "`~a' is not a symbol." x)))

(define-setf-expander symbol-plist (x)
  (let ((g!x (gensym))
        (g!value (gensym)))
    (values (list g!x)
            (list x)
            (list g!value)
            `(set-symbol-plist ,g!value ,g!x)
            `(symbol-plist ,g!x))))

(defun get (symbol indicator &optional default)
  (getf (symbol-plist symbol) indicator default))