[Q] Enter a group, show an article -- how to?

[Q] Enter a group, show an article -- how to?

[Kai Grossjohann]

Given a group name and an article number, I would like to enter this
group ephemerally and show exactly the given article plus the thread
that contains this article.

I am now doing the following:

,-----
| (gnus-group-read-ephemeral-group
|  GROUP                     
|  BACKEND                   
|  t                                  ; activate
|  (cons (current-buffer)    
|        'summary)                    ; window config
|  nil)                      
| (gnus-summary-limit (list ARTICLE-NUMBER))
| (gnus-summary-refer-thread)
`-----

This has a few problems, though.  For one thing, it is slow for large
groups, as it has got to fetch all article headers (not much of a
problem) and generate the complete summary buffer (this is the
time-killer, right here!) before throwing most of it away.  Is there a
way that I can enter the group without generating a huge summary
buffer first?  (Or should I wait for a new Gnus version which will
have a command for entering a group and displaying a specified set of
articles?)

The second problem with the above code is that it will ask the user
how many articles to receive, if the group is large.  An obvious
workaround is to temporarily bind gnus-large-newsgroup.  But is this a
good solution, too?

Oh, and another question: is the variable gnus-current-select-method
the right way of finding out the backend that the current summary
buffer belongs to?

And yet another question: is the variable gnus-article-current the
right way of finding the current article number?  Does it point to the
article that is being shown in the *Article* buffer or to the article
under point?  If the former, how to I find out the latter?

How could I have found each or any of the above without asking?  I
tried the time-tried UTSL method but I was lacking understanding of
what was going on...

kai
-- 
You cannot fix a machine by just power-cycling it with no
understanding of what is going wrong.  (Tom Knight)

Re: [Q] Enter a group, show an article -- how to?

[Lars Magne Ingebrigtsen]

Kai Grossjohann <grossjohann@amaunet.cs.uni-dortmund.de> writes:

> This has a few problems, though.  For one thing, it is slow for large
> groups, as it has got to fetch all article headers (not much of a
> problem) and generate the complete summary buffer (this is the
> time-killer, right here!) before throwing most of it away.  Is there a
> way that I can enter the group without generating a huge summary
> buffer first?

I've now added a SELECT-ARTICLES parameter to the ephemeral function
that will let you generate a summary buffer with only the requested
articles in it.

> The second problem with the above code is that it will ask the user
> how many articles to receive, if the group is large.  An obvious
> workaround is to temporarily bind gnus-large-newsgroup.  But is this a
> good solution, too?

I think so; yes.

> Oh, and another question: is the variable gnus-current-select-method
> the right way of finding out the backend that the current summary
> buffer belongs to?

Yes.

> And yet another question: is the variable gnus-article-current the
> right way of finding the current article number?  Does it point to the
> article that is being shown in the *Article* buffer or to the article
> under point?

The former.

> If the former, how to I find out the latter?

(gnus-summary-article-number) will return the article under point. 

> How could I have found each or any of the above without asking?  I
> tried the time-tried UTSL method but I was lacking understanding of
> what was going on...

Uhm...  I think asking was the most cost-effective way of finding
out. 

-- 
(domestic pets only, the antidote for overdose, milk.)
  larsi@gnus.org * Lars Magne Ingebrigtsen