Initial revision

1 files changed, 49 insertions, 0 deletions

diff --git a/chess-session.el b/chess-session.el
new file mode 100644
index 0000000..6f0dde4
--- /dev/null
+++ b/chess-session.el
@@ -0,0 +1,49 @@
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;
+;; Manage a chess playing/viewing session
+;;
+;; $Revision$
+
+;;; Commentary:
+
+(defun chess-session-create ()
+  (cons nil nil))
+
+(defun chess-session-add-listener (session listener &optional front)
+  (if (or front (not (cdr session)))
+      (setcdr session (cons (cons listener nil)
+			    (cdr session)))
+    (nconc session (list (cons listener nil)))))
+
+(defun chess-session-remove-listener (session listener)
+  (setcdr session (delq (assq listener (cdr session))
+			(cdr session))))
+
+(defun chess-session-data (session sym)
+  (cdr (assq sym (car session))))
+
+(defun chess-session-set-data (session sym value)
+  (let ((entry (assq sym (car session))))
+    (if entry
+	(setcdr entry value)
+      (setcar session (cons (cons sym value)
+			    (car session))))))
+
+(defun chess-session-del-data (session sym)
+  (setcar session (delq (assq sym (car session))
+			(car session))))
+
+(defun chess-session-event (session event &rest args)
+  (let ((listeners (cdr session)) result)
+    (while (and (or (eq event 'initialize)
+		    (null result)) listeners)
+      (setq result (apply (caar listeners) session (cdar listeners)
+			  event args))
+      (if (eq event 'initialize)
+	  (setcdr (car listeners) result))
+      (setq listeners (cdr listeners)))
+    result))
+
+(provide 'chess-session)
+
+;;; chess-session.el ends here