Re: One-off history for read-string

[Marcin Borkowski <mbork@mbork.pl>]

On 2015-09-26, at 04:33, John Mastro <john.b.mastro@gmail.com> wrote:

> Emanuel Berg <embe8573@student.uu.se> wrote:
>
>> > However, I don't care about /writing/ it to some
>> > variable in Emacs, since the new entry will be
>> > uploaded to the server anyway, and taken from there
>> > the next time, together with the rest of
>> > the history.
>>
>> So then, what does it matter?
>
> He wants history to be available to the user (e.g. `M-p'), but he wants
> that history to come from a server rather than be accumulated in the
> usual way. So the history on the server is likely changing over time,
> but from the Lisp code's perspective it's conceptually a new list each
> time.

Yes.

> Something like this, if I understand him correctly:

Yes, you do.

>     (defvar readonly-history)
>
>     (defun get-history-list-from-server ()
>       ;; Imagine we fetch this list of HTTP
>       (list "foo" "bar" "baz" "quux"))
>
>     (defun my-read-string (prompt)
>       (let ((readonly-history (get-history-list-from-server)))
>         (read-string prompt nil 'readonly-history)))

And this is exactly what I'm doing now, modulo variable names (and
get-history-list-from-server, which is really

(mapcar #'get-piece-of-history a-big-datastructure-got-from-the-server)

or really

(mapcar #'get-piece-of-history
        (cdr
          (assoc 'datastructure-key
                 an-even-bigger-alist-of-similar-but-unrelated-datastructures-got-from-the-server)

Best,

-- 
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Faculty of Mathematics and Computer Science
Adam Mickiewicz University