can be done with Javascript?

doc/forum/appear_if_you_are_login_or_not_in_a_page.mdwn

@@ -14,3 +14,11 @@ Xan.
 > if at all. --[[Schmonz]]
 
 >> Thanks a lot, Xan.
+
+>>> Another possible trick would be to use some Javascript to make a
+>>> "who am I?" AJAX request to the CGI (the CGI would receive the
+>>> session cookie, if any, and be able to answer). Obviously, this
+>>> wouldn't work for users who've disabled Javascript, but since it's
+>>> non-essential, that's not so bad. You'd need to
+>>> [[write_a_plugin|plugins/write]] to add a suitable CGI action,
+>>> perhaps ?do=whoami, and insert the Javascript. --[[smcv]]