role/anon

indenting2.el

@@ -1,6 +1,6 @@
 ;; Emacs indent settings
 (progn
   (mapcar #'(lambda (x) (put x 'scheme-indent-function 1))
-	  '(transition sequence-actions))
+	  '(role/anon transition sequence-actions))
   (mapcar #'(lambda (x) (put x 'scheme-indent-function 2))
 	  '(role role/fresh yield)))

os2.rkt

@@ -34,6 +34,7 @@
 					      transition/c)))
 
 	 role
+	 role/anon
 	 role/fresh
 	 (except-out (struct-out add-role) add-role)
 	 (rename-out [make-add-role add-role])
@@ -267,6 +268,11 @@
 		     topics-expr
 		     (handlers presence-handler absence-handler message-handler)))])))
 
+;; For use when you don't care to invent a name for a role.
+(define-syntax-rule (role/anon topic pieces ...)
+  (role (gensym 'anonymous-role) topic pieces ...))
+
+;; Invents a role name for you, and binds it to pre-eid-var.
 (define-syntax-rule (role/fresh pre-eid-var rest ...)
   (let ((pre-eid-var (gensym 'role)))
     (role pre-eid-var rest ...)))