Re: Testers wanted: New gnus backend nnselect

[Eric Abrahamsen <eric@ericabrahamsen.net>]

Andrew Cohen <cohen@bu.edu> writes:

> TLDR: Please test the new feature found on the git repository at
> feature/gnus-select.

Very cool! Later this week I'll make another copy of the search-language
branch that's rebased onto this one.

[...]

> Why is it invasive? It is a generalization of the code I wrote many
> years ago re-working the nnir backend. Consequently in this new format
> nnir has CEASED to be a backend and is now just some code for searching
> indices. Searching in gnus now works by creating an ephemeral nnselect
> group where the list of articles is obtained from nnir.

Once this has landed, I hope we can rename nnir.el to gnus-search.el,
and drop the "nnir" term altogether.

> I have so far mostly tested this with imap. Since it is essentially
> backend independent it should just work, but this needs to be tested.
>
> So please, please, give it some testing. The new code can be found in a
> branch, feature/gnus-select, in the emacs git repository. Just check it
> out, make, and give it a whirl.
>
> Ideally if you just continue searching as you have always done you won't
> notice much of a difference (except that referring threads is a bit
> different---more on that later). This is the first thing that needs
> testing.

I've started on a gnus-search-thread method for the search engines -- in
fact, the majority of them can already handle searching by thread.
Ideally `nnselect-request-thread' could then become engine-agnostic, and
only punt if the engine in question doesn't implement the
`gnus-search-thread' method.

> Once you are confident that this is working you can try new
> things. Firstly make some permanent nnselect groups. You do this as you
> would for any group: start with "G m" (gnus-group-make-group) from the
> Group buffer; give it a name; choose the method "nnselect"; it will then
> query for a function; and then an argument. The function will be applied
> to the argument (with funcall) to generate the list of articles. A good
> choice for the function is nnir-run-query, and the argument can be an
> appropriate search query (some examples below). It can also be any
> function that returns a vector, each entry of which is a 3-vector formed
> from [Group, Number, Score] (the group containing the actual article;
> the number of the article in that group; a score, which is supposed to
> help in sorting but is largely unused at this point---just set it to 1
> if you are unsure). So for a silly example the function could be the
> identity, and the arg this vector.

I think that, to maximize chances of people actually testing this, it
would be best to provide a ready-made
`gnus-group-make-persistent-search-group' function (or call it
whatever), and give it a keybinding. Say:

"G g": gnus-group-make-ephemeral-search-group
"G G": gnus-group-make-persistent-search-group

I know this or something like it is on the todo list, but I'd recommend
doing this first so people are more likely to give it a whirl...

Eric