unofficial mirror of help-gnu-emacs@gnu.org
 help / color / mirror / Atom feed
From: Sergei Organov <osv@javad.com>
To: help-gnu-emacs@gnu.org
Subject: Re: Problem advising nreverse.
Date: Tue, 15 Dec 2009 15:02:39 +0300	[thread overview]
Message-ID: <hg7tsv$io$1@ger.gmane.org> (raw)
In-Reply-To: hg7gqf$n9n$1@ger.gmane.org

Kevin Rodgers <kevin.d.rodgers@gmail.com> writes:

> [I'm responding to this message, because subsequently the thread spun out of
> control beyond my comprehension.]
>
> Sergei Organov wrote:
>> pjb@informatimago.com (Pascal J. Bourguignon) writes:
> ...
>>> Redefining nreverse and reloading the ewoc-collect function would help
>>> as indicated...
>>
>> Yeah, but:
>>
>> 1. I don't really want `nreverse' to be always redefined.
>
> If you know the bug is in ewoc, you don't want nreverse redefined ever.
>
>> 2. I don't know how to reload `ewoc-collect' (from elisp) provided it's
>>    already byte-compiled.
>
> Put the new defun in a file and explicitly reload it.

Copy-paste the original and fix that? This has its own drawbacks. Think
what will happen when new version of the package with incompatible
function appears.

>> Here what I've actually originally tried (that didn't work):
>>
>> (defadvice ewoc-collect (around fix-ewoc-collect activate)
>>   "Fix buggy `ewoc-collect' by reversing its result provided it
>>    was altered by `nreverse'."
>>   (let ((last-nreverse-result))
>>     (unwind-protect
>>         (progn
>>           (defadvice nreverse (after notice-nreverse activate)
>>             (setq last-nreverse-result ad-return-value))
>>           ad-do-it)
>
> ad-do-it is not a variable: it is a form that can only be meaningfully
> referenced *within* a defadvice form.

But it *is* within 'fix-ewoc-collect' defadvice form (look at top-level).

>
>>       (ad-unadvise 'nreverse))
>>     (if (eq last-nreverse-result ad-return-value)
>>         (setq ad-return-value (nreverse ad-return-value)))))
>
> I don't understand: How can you determine whether any value "was
> altered by nreverse"?  That is not Lispish thinking.

Yeah, probably it is not Lispish. Another option was to make 'nreverse'
a no-op for duration of 'ewoc-collect' call, but that didn't work
either, apparently due to the same reason defadvice of nreverse doesn't
work.

-- 
Sergei.





  reply	other threads:[~2009-12-15 12:02 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.12764.1260538816.2239.help-gnu-emacs@gnu.org>
2009-12-12 12:18 ` Problem advising nreverse Pascal J. Bourguignon
2009-12-14 11:07   ` Sergei Organov
     [not found]   ` <mailman.12932.1260788943.2239.help-gnu-emacs@gnu.org>
2009-12-14 13:01     ` Pascal J. Bourguignon
2009-12-14 15:05       ` Sergei Organov
2009-12-15  8:19         ` Kevin Rodgers
2009-12-15 12:02           ` Sergei Organov [this message]
     [not found]       ` <mailman.12940.1260803316.2239.help-gnu-emacs@gnu.org>
2009-12-14 15:23         ` Pascal J. Bourguignon
2009-12-14 16:01           ` Sergei Organov
     [not found]           ` <mailman.12941.1260806509.2239.help-gnu-emacs@gnu.org>
2009-12-14 17:56             ` Pascal J. Bourguignon
2009-12-14 19:59               ` Sergei Organov
     [not found]               ` <mailman.12952.1260820780.2239.help-gnu-emacs@gnu.org>
2009-12-15  1:47                 ` Pascal J. Bourguignon
2009-12-15 12:06                   ` Sergei Organov
     [not found]                   ` <mailman.13009.1260879016.2239.help-gnu-emacs@gnu.org>
2009-12-15 19:54                     ` Pascal J. Bourguignon
2009-12-15 20:38                   ` Sergei Organov
     [not found]                   ` <mailman.13027.1260909564.2239.help-gnu-emacs@gnu.org>
2009-12-15 21:12                     ` Barry Margolin
2009-12-16 11:27                       ` Sergei Organov
     [not found]                       ` <mailman.13051.1260962896.2239.help-gnu-emacs@gnu.org>
2009-12-17 16:52                         ` Barry Margolin
2009-12-11 13:22 Sergei Organov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: https://www.gnu.org/software/emacs/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='hg7tsv$io$1@ger.gmane.org' \
    --to=osv@javad.com \
    --cc=help-gnu-emacs@gnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
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).