Trying to start ielm results in the lisp backtrace below. A possible fix is attached. Signaling: (setting-constant : nil) (setq : nil) ) inferior-emacs-lisp-mode() (save-excursion (set-buffer (get-buffer-create "*ielm*")) (inferior-emacs-lisp-mode)) ) (if (comint-check-proc "*ielm*") nil (save-excursion (set-buffer ...) (inferior-emacs-lisp-mode))) ) (lambda nil "Interactively evaluate Emacs Lisp expressions.\nSwitches to the buffer `*ielm*', or creates it if it does not exist." (interactive) (if (comint-check-proc "*ielm*") nil (save-excursion ... ...)) (pop-to-buffer "*ielm*"))() call-interactively(ielm) command-execute(ielm t) execute-extended-command(nil) call-interactively(execute-extended-command) recursive-edit() byte-code("..." [pop-to-buffer debugger-buffer erase-buffer t 50 print-length print-escape-newlines standard-output backtrace debugger-mode re-search-forward "\n[* ] debug(" 1 debugger-reenable debugger-args (lambda debug) "Entering:\n" debug backtrace-debug 3 delete-char ?\* 0 exit "Return value: " debugger-value prin1 ?\n ?\ error "Signaling: " "Beginning evaluation of function call form:\n" nil message "" buffer-read-only inhibit-trace recursive-edit] 3) debug(error (undefined-keystroke-sequence [#<keypress-event control-X> #<keypress-event control-A>])) Here is the patch: --- xemacs/xemacs-21.0-b47/packages/lisp/xemacs-devel/ielm.el Sun Jan 25 20:24:59 1998 +++ ./ielm.el Sat Jul 11 23:29:57 1998 ＠＠ -301,15 +301,15 ＠＠ (if (ielm-is-whitespace (substring ielm-string ielm-pos)) ;; need this awful let convolution to work around ;; an Emacs bug involving local vbls and let binding - (let ((:save :) - (::save ::) - (:::save :::)) + (let ((ielm-:save ielm-:) + (ielm-::save ielm-::) + (ielm-:::save ielm-:::)) (save-excursion (set-buffer ielm-working-buffer) (condition-case err - (let ((: :save) - (:: ::save) - (::: :::save) + (let ((ielm-: ielm-:save) + (ielm-:: ielm-::save) + (ielm-::: ielm-:::save) (ielm-obuf (current-buffer))) (setq ielm-result (eval ielm-form)) (setq ielm-wbuf (current-buffer)) ＠＠ -346,9 +346,9 ＠＠ (setq ielm-output (concat ielm-output "*** " ielm-error-type " *** ")) (setq ielm-output (concat ielm-output ielm-result))) ;; There was no error, so shift the ::: values - (setq ::: ::) - (setq :: :) - (setq : ielm-result)) + (setq ielm-::: ielm-::) + (setq ielm-:: ielm-:) + (setq ielm-: ielm-result)) (setq ielm-output (concat ielm-output "\n")))) (setq ielm-output (concat ielm-output ielm-prompt)) (comint-output-filter (ielm-process) ielm-output))) ＠＠ -386,9 +386,9 ＠＠ * \\[comint-dynamic-complete] completes Lisp symbols (or filenames, within strings), or indents the line if there is nothing to complete. -During evaluations, the values of the variables `:', `::', and `:::' -are the results of the previous, second previous and third previous -evaluations respectively. +During evaluations, the values of the variables `ielm-:', `ielm-::', and +`ielm-:::' are the results of the previous, second previous and third +previous evaluations respectively. The current working buffer may be changed (with a call to `set-buffer', or with \\[ielm-change-working-buffer]), and its value ＠＠ -436,12 +436,12 ＠＠ (setq fill-paragraph-function 'lisp-fill-paragraph) ;; Value holders - (setq : nil) - (make-local-variable ':) - (setq :: nil) - (make-local-variable '::) - (setq ::: nil) - (make-local-variable ':::) + (setq ielm-: nil) + (make-local-variable 'ielm-:) + (setq ielm-:: nil) + (make-local-variable 'ielm-::) + (setq ielm-::: nil) + (make-local-variable 'ielm-:::) ;; font-lock support (make-local-variable 'font-lock-defaults)