comint-mode broken in GNU Emacs 21.2.1?

comint-mode broken in GNU Emacs 21.2.1?

[Vincent Montressor]

I'm having trouble using comint-mode under GNU Emacs 21.2.1:

% emacs -nw -q

	M-x compile

Change compile command to something that accepts interactive input, such as cat:

	C-a C-k cat RET

Go to the end of the compilation buffer and enter comint-mode:

	C-x o M->

	M-x comint-mode

Type something and hit RET:

	hello, world RET

Emacs issues the following error:

	error in process filter: Wrong type argument: markerp, nil

Does anyone know how to fix this?

Re: comint-mode broken in GNU Emacs 21.2.1?

[Stefan Monnier]

> 	error in process filter: Wrong type argument: markerp, nil
> Does anyone know how to fix this?

The usual way: set debug-on-error, reproduce the error, look at the
backtrace, if you don't know what to do then, post the backtrace for more
info, ...


        Stefan

Re: comint-mode broken in GNU Emacs 21.2.1?

[Kevin Rodgers]

[-- Attachment #1: Type: text/plain, Size: 657 bytes --]

Vincent Montressor wrote:

> I'm having trouble using comint-mode under GNU Emacs 21.2.1:
> 
> % emacs -nw -q
> 
> 	M-x compile
> 
> Change compile command to something that accepts interactive input, such as cat:
> 
> 	C-a C-k cat RET
> 
> Go to the end of the compilation buffer and enter comint-mode:
> 
> 	C-x o M->
> 
> 	M-x comint-mode
> 
> Type something and hit RET:
> 
> 	hello, world RET
> 
> Emacs issues the following error:
> 
> 	error in process filter: Wrong type argument: markerp, nil


I'll bet you're using my compile-input.el hack written way back in 1996.
Try this version, which adds comint-accum-marker to the comint-mode emulation:


[-- Attachment #2: compile-input.el --]
[-- Type: text/plain, Size: 1391 bytes --]

;;; compile-input.el

(defun compile-enable-input ()
  "Enable user input to *compilation* buffers.
To do so, add this function to compilation-mode-hook."
  ;; Emulate comint-mode:
  (require 'comint)
  (set (make-local-variable 'comint-input-ring)
       (make-ring comint-input-ring-size))
  (set (make-local-variable 'comint-last-input-start)
       (make-marker))
  (set-marker comint-last-input-start (point-min))
  (set (make-local-variable 'comint-last-input-end)
       (make-marker))
  (set-marker comint-last-input-end (point-min))
  (set (make-local-variable 'comint-last-output-start)
       (make-marker))
  (set-marker comint-last-output-start (point-max))
  (set (make-local-variable 'comint-accum-marker)
       (make-marker))
  (set-marker comint-accum-marker nil)
  (add-hook (make-local-variable 'pre-command-hook)
	    'comint-preinput-scroll-to-bottom)
  ;; Move point to EOB on input:
  (set (make-local-variable 'comint-scroll-to-bottom-on-input)
       'this)
  ;; Restore useful bindings for input:
  (local-unset-key " ")			; was scroll-up
  (local-unset-key "\^?")		; was scroll-down
  ;; Add bindings to send input to compilation process:
  (local-set-key "\C-c\C-d" 'comint-send-eof)
  (local-set-key "\C-m" 'comint-send-input)
  ;; Enable input:
  (set (make-local-variable 'compile-disable-input) nil))

(add-hook 'compilation-mode-hook 'compile-enable-input)

[-- Attachment #3: Type: text/plain, Size: 151 bytes --]

_______________________________________________
Help-gnu-emacs mailing list
Help-gnu-emacs@gnu.org
http://mail.gnu.org/mailman/listinfo/help-gnu-emacs

Re: comint-mode broken in GNU Emacs 21.2.1?

[Vincent Montressor]

"Stefan Monnier" <monnier@iro.umontreal.ca> wrote in message news:<jwvy8wlu93d.fsf@vor.iro.umontreal.ca>...
> > 	error in process filter: Wrong type argument: markerp, nil
> > Does anyone know how to fix this?
> 
> The usual way: set debug-on-error, reproduce the error, look at the
> backtrace, if you don't know what to do then, post the backtrace for more
> info, ...

The compile-input.el solution posted by Kevin Rodgers solved the
problem for me (thanks!), so I am back in business.  (Indeed, this
solution is even nicer than using comint-mode, since I don't have to
change modes in the compilation buffer.)

Just out of curiosity, I did as you suggested above, using comint-mode
as before, and got this backtrace:

Debugger entered--Lisp error: (wrong-type-argument markerp nil)
  marker-position(nil)
  compilation-filter(#<process compilation> "hello, world\n")

I can't afford the time to explore it further now, especially since my
problem is solved, but anyone else who's interested now has that as a
starting point.

Thanks to both of you for your assistance.