Re: What is a "virtual" group?

[Dave Abrahams <dave@boostpro.com>]

on Tue Dec 25 2012, Dave Abrahams <dave-AT-boostpro.com> wrote:

>>>>> * Does the check for virtual-ness in gnus-warp-to-article actually
>>>>>   belong there?  After all, real groups shouldn't implement the
>>>>>   warp-to-article backend function, should they?
>>>>
>>>> I don't know.
>>>
>>> Would you be open to a patch that removes the check?
>>
>> I'm not familiar with that code.
>
> Sorry, I don't know how to interpret your answer.

Bump on this.  I get a sense the length of the message may have put you
off.  I'll try to make this super-simple for you:

* I would like to remove the check for virtual-ness in
  gnus-warp-to-article.

* I believe that removal to be OK.  I'll test it here, of course, and
  I'm a daily user of warping.

* If I don't find any problems with it, would that be enough to convince
  you that the change is OK and to accept the patch?

* If not, what would it take to convince you to accept the patch?

All I really need from you is answers to the last two bullets above

The rest of what's below is background, designed to convince you it
might be worth taking a risk on such a change to get a really cool
feature, but you can ignore it if you're too busy.

> I am trying to figure out how to contribute a really cool (and for me,
> essential) piece of functionality to Gnus: the ability to, given a
> message-id, find and display the message in the context of the entire
> thread in which that message participates, even across groups.  Of
> course I'm presuming you think that's worth having in Gnus, but I could
> be wrong.  If so, just tell me and I'll stop pestering you.
>
> I have implemented something that works, but currently requires making
> nndoc groups virtual or disabling that check.  You've already said that
> making nndoc groups virtual is inappropriate.  If disabling the check is
> appropriate, that would solve the problem easily.  
>
> The other possible approach would be to discover a way to implement the
> following function using some kind of virtual group (instead of nndoc).
> I think that's probably the best approach but I have tried myself many
> times and failed, and I have asked here many times for guidance without
> success... so I eventually gave up.
>
> #+begin_src lisp
> (defun gnus-goto-article (message-id)
>   (with-temp-buffer
>     (erase-buffer)
>     ;; Insert dummy article
>     (insert (format "From nobody Tue Sep 13 22:05:34 2011\n\n"))
>     (gnus-group-read-ephemeral-group
>      message-id
>      `(nndoc ,message-id
>              (nndoc-address ,(current-buffer))
>              (nndoc-article-type mbox))
>      :activate
>      (cons (current-buffer) gnus-current-window-configuration)
>      (not :request-only)
>      '(-1) ; :select-articles
>      (not :parameters)
>      0     ; :number
>      )
>     (gnus-summary-refer-article message-id)
>     ))
> #+end_src

-- 
Dave Abrahams
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