Re: Org-cite: Replace basic follow-processor with transient menu?

[Ihor Radchenko <yantar92@posteo.net>]

Jonas Bernoulli <jonas@bernoul.li> writes:

>>   :set (lambda (option-name new-value)
>>          (eval
>>           `(transient-define-prefix org-cite-basic-follow (citation &optional prefix)
>>              "Follow a citation reference.
> ...
>
> (transient-define-prefix org-cite-basic-follow (citation &optional prefix)
>   [org-cite-basic-follow-actions]
> ...

This is more compact indeed. Thanks!

> I use something similar in Forge (forge--lists-group et al.), but
> there the purpose is to share groups between different prefixes, not
> to make them customizable.

And this is the problem. See the above :set we have to add in order to
re-evaluate the prefix definition.

It would be nice if the layout could be calculated dynamically rather
than frozen in place in the "defun".

> To let users choose what commands to offer in the menu, I would
> recommend directing users towards Transient's "layer" mechanism instead
> of adding an option.
>
> See [[info:transient#Enabling and Disabling Suffixes]].  To try it enter
> any prefix (magit-diff would do) and type "C-x l".  Usage information is
> displayed after that.

This will indeed help with customizing *pre-existing suffixes*. However,
what we really want here is different - we want a minimal set of
suffixes to be provided by Org mode, and more suffixes to be contributed
by individual packages or by users themselves.

In other words, we need some way to add new suffixes to the
org-cite-basic-follow prefix menu.

>> :scope (list citation prefix)
>
> Shouldn't that be just be
>   :scope citation
> and then
>   (interactive (list (magit-scope)))
> to access it?

We want the [suffix] commands to have information about the prefix argument used
to call `org-cite-basic-follow'.

> Yes, obviously you have to call transient-scope somewhere.
>
> I haven't seen enough of the commands you want to add as suffixes to
> know whether it would make sense, and is even possible, to add an
> abstraction, and the few examples I have seen already contain
> non-commands and "find as pdf" doesn't even exist as a named function.
>
> That being said, if there are multiple commands like
>
>   (defun do-something-with-citation (citation)
>     (interactive (list (read-citation "Do something with citation: ")))
>     ...)
>
> it might make sense to change read-citation like this
>
>   (defun read-citation (prompt)
>     (if (eq transient-current-prefix 'org-cite-basic-follow)
>         (org-element-property :key (transient-scope))
>       ...old body here...))

This is precisely what I want to avoid.

What we want is having normal commands/functions and then allowing to
add them as suffixes without having to change their interactive spec or
source code in general.

Currently, if we want suffix that is calling a function not specially
designed with transient support in mind, we need to do the ugly juggle
like

    (transient-append-suffix 'org-cite-basic-follow "b"
      '("g" "goto"
	(lambda (citation prefix)
	  (interactive (transient-scope))
          (org-cite-basic-goto citation prefix))))

It would be so much nicer to write something simpler like

(transient-define-prefix org-cite-basic-follow (citation &optional prefix)
		   "Follow a citation reference.
      The contents of this transient menu is set in org-cite-basic-follow-actions."
		   [["Open"
                     ("b" "bibliography entry" org-cite-basic-goto :args (transient-args))]]
		   (interactive)
		   (if (or org-cite-basic-follow-ask prefix)
                       ;; Imaginary :args slot
		       (transient-setup 'org-cite-basic-follow nil nil :args (list citation prefix))
		     (org-cite-basic-goto citation prefix)))

-- 
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
Support Org development at <https://liberapay.com/org-mode>,
or support my work at <https://liberapay.com/yantar92>