(elp-instrument-package): Don't allow empty prefixes.

diff --git a/lisp/emacs-lisp/elp.el b/lisp/emacs-lisp/elp.el
index 42dc1bc070bbc05ac9cf250d48e43a725abb7fc4..af189126a0979060ae958d12369a104a5ae501e5 100644 (file)
--- a/lisp/emacs-lisp/elp.el
+++ b/lisp/emacs-lisp/elp.el
@@ -323,6 +323,8 @@ For example, to instrument all ELP functions, do the following:
 
     \\[elp-instrument-package] RET elp- RET"
   (interactive "sPrefix of package to instrument: ")
+  (if (zerop (length prefix))
+      (error "Instrumenting all Emacs functions would render Emacs unusable."))
   (elp-instrument-list
    (mapcar
     'intern