Re: Trigger action at exit?

[John Trammell]

On Sun, Mar 2, 2008 at 11:25 AM, Ludovic Courtès <address@hidden> wrote:
>  One possibility is to catch the `quit' exception:
>
>   guile> (catch 'quit
>            (lambda ()
>              ;; the function that may `exit'
>              (exit 1))
>            (lambda (key . args)
>              ;; the handler
>              (format #t "quit: ~a~%" args)))
>   quit: (1)
>

At first blush this looked like a good answer, but it appears to be
calling the handler at the *beginning* of the script, not the end:

(define index 0)
(define has-plan #f)

(define (cleanup)
  (simple-format #t "has-plan: ~a~%" has-plan)
  (simple-format #t "1..~a~%" index))

(catch 'quit
       (lambda () (exit 1))
       (lambda (key .  args)
         (begin (format #t "in handler~%")
                (format #t "key:~a args:~a~%" key args)
                (cleanup))))

(set! has-plan #t)
(format #t "fiddle dee dee~%")

; output is:
; in handler
; key:quit args:(1)
; has-plan: #f
; 1..0
; fiddle dee dee

I find it interesting that "quit" appears to be a special key to
"catch", but I can't find it documented anywhere (I did find other
keys documented at
http://home.thezone.net/~gharvey/guile/qdocs/html/qdocs_6.html).
Googling for "guile catch key quit" (plus similar variations on
"exception(s)" and "atexit") brings no enlightenment.

Also various attempts to flush stdout do not affect the output
sequence.  Am I doing something wrong?  Should this work?

Thanks for the help,
JT