unofficial mirror of emacs-devel@gnu.org 
 help / color / mirror / code / Atom feed
* Q: while loop in impl of error and user-error
@ 2013-10-29  1:24 T.V. Raman
  2013-10-29 21:06 ` Stefan Monnier
  0 siblings, 1 reply; 4+ messages in thread
From: T.V. Raman @ 2013-10-29  1:24 UTC (permalink / raw)
  To: emacs-devel

I was surprized to see the while loop in the body of function
'error and 'user-error

why is the call to signal enclosed in a (while t ...) loop?

(defun user-error (format &rest args)
  "Signal a pilot error, making error message by passing all args to `format'.
In Emacs, the convention is that error messages start with a capital
letter but *do not* end with a period.  Please follow this convention
for the sake of consistency.
This is just like `error' except that `user-error's are expected to be the
result of an incorrect manipulation on the part of the user, rather than the
result of an actual problem."
  (while t
    (signal 'user-error (list (apply #'format format args)))))
-- 

--



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Q: while loop in impl of error and user-error
  2013-10-29  1:24 Q: while loop in impl of error and user-error T.V. Raman
@ 2013-10-29 21:06 ` Stefan Monnier
  2013-10-29 23:14   ` Jarek Czekalski
  0 siblings, 1 reply; 4+ messages in thread
From: Stefan Monnier @ 2013-10-29 21:06 UTC (permalink / raw)
  To: T.V. Raman; +Cc: emacs-devel

> why is the call to signal enclosed in a (while t ...) loop?

Can't remember, I think it was just copied from `error'.  As for why
it was there in `error', I don't know either.
We should probably just remove them.


        Stefan



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: Q: while loop in impl of error and user-error
  2013-10-29 21:06 ` Stefan Monnier
@ 2013-10-29 23:14   ` Jarek Czekalski
  2013-10-30  9:13     ` T.V. Raman
  0 siblings, 1 reply; 4+ messages in thread
From: Jarek Czekalski @ 2013-10-29 23:14 UTC (permalink / raw)
  To: emacs-devel

Maybe it is a smart way of telling the same that is in the docs of 
signal: this function does not return.

The code is there since 1990.

http://bzr.savannah.gnu.org/lh/emacs/trunk/revision/115

However seems like other calls to signal do not use this interesting 
construct.

Jarek




^ permalink raw reply	[flat|nested] 4+ messages in thread

* Q: while loop in impl of error and user-error
  2013-10-29 23:14   ` Jarek Czekalski
@ 2013-10-30  9:13     ` T.V. Raman
  0 siblings, 0 replies; 4+ messages in thread
From: T.V. Raman @ 2013-10-30  9:13 UTC (permalink / raw)
  To: Jarek Czekalski, emacs-devel

I would still nuke that loop -- the signal docs are clear that
signal does not return; this while loop as written is just
mysterious
-- 

-- 


On 10/29/13, Jarek Czekalski <jarekczek@poczta.onet.pl> wrote:
> Maybe it is a smart way of telling the same that is in the docs of
> signal: this function does not return.
>
> The code is there since 1990.
>
> http://bzr.savannah.gnu.org/lh/emacs/trunk/revision/115
>
> However seems like other calls to signal do not use this interesting
> construct.
>
> Jarek
>
>
>



^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2013-10-30  9:13 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-10-29  1:24 Q: while loop in impl of error and user-error T.V. Raman
2013-10-29 21:06 ` Stefan Monnier
2013-10-29 23:14   ` Jarek Czekalski
2013-10-30  9:13     ` T.V. Raman

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/emacs.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).