I've just added support for imenu <http://camdez.com/blog/2013/11/28/emacs-rapid-buffer-navigation-with-imenu/> in the Emacs mode. It seems to work pretty well, and takes it a bit closer to making it a proper "APL IDE". :-)
If you really want to go deep into configuring imenu, you can check out the EmacsWiki page on it <http://www.emacswiki.org/emacs/ImenuMode>. Regards, Elias
