Yeah, Slime does this and without ctags, I believe most lisps keep track of the location of definitions in source.<p>But what's a definition?  Slime does this for defun/defvar etc, but not for things defined with, say, hunchentoot's define-easy-handler.  Can you tell your IDE to take me to that location in a single keystroke?  Maybe Slime supports adding definition types, I have no idea.  Or maybe it throws up its hands because of the potential naming conflicts.<p>All this makes you wonder whether Lisp is too powerful for any IDE to keep up.