Incorporating new things into completions

Incorporating new things into completions

[Psionic K]

I want to augment `switch-to-buffer' candidates to contain a list of
exotic fruits.  Presumably the downstream handler for buffers has no
idea what to do with fruits, so I need to provide some alternative
handler.

Has this infrastructure been built into Emacs or is it exclusive to
completion packages at this time?   If Emacs provides facilities for
this kind of thing, what vocabulary should I become familiar with?

Re: Incorporating new things into completions

[Emanuel Berg]

Psionic K wrote:

> I want to augment `switch-to-buffer' candidates to contain
> a list of exotic fruits. Presumably the downstream handler
> for buffers has no idea what to do with fruits, so I need to
> provide some alternative handler.
>
> Has this infrastructure been built into Emacs or is it
> exclusive to completion packages at this time? If Emacs
> provides facilities for this kind of thing, what vocabulary
> should I become familiar with?

I have something to that extent, but instead of a list, it
matches a regexp. Don't know if this is already available
somewhere else but that wouldn't come as a surprise.

;;; -*- lexical-binding: t -*-
;;
;; this file:
;;   https://dataswamp.org/~incal/emacs-init/switch-to-buffer-regexp.el

(require 'cl-lib)
(require 'buc)

(defun switch-to-buffer-regexp (buf-re)
  (let*((ori-buf (buffer-name (current-buffer)))
        (hits    (cl-remove-if-not
                   (lambda (b) (string-match buf-re b)) (buffer-names)) ))
    (when hits
      (let ((new-hits (cl-remove ori-buf hits)))
        (when new-hits
          (when (string-match buf-re ori-buf)
            (bury-buffer ori-buf) )
          (switch-to-buffer (car new-hits)) )))))

;; try it!
;; (require 'gnus)
;; (dotimes (i 4) (gnus-post-news 'post "")) ; create 4 posts

(global-set-key "\C-cu" (lambda () (interactive) (switch-to-buffer-regexp "\*unsent posting\*.*")))
;; hit again to iterate

(provide 'switch-to-buffer-regexp)

Some more example use cases, some of which I use every day:

  https://dataswamp.org/~incal/emacs-init/switch-to-buffer.el

Ugh, for it to work this is needed as well from yet another file

(defun buffer-names ()
  "Get the names of all open buffers, as strings."
  (mapcar #'buffer-name (buffer-list)) )

https://dataswamp.org/~incal/emacs-init/buc.el

-- 
underground experts united
https://dataswamp.org/~incal

Re: Incorporating new things into completions

[Philip Kaludercic]

Psionic K <psionik@positron.solutions> writes:

> I want to augment `switch-to-buffer' candidates to contain a list of
> exotic fruits.  Presumably the downstream handler for buffers has no
> idea what to do with fruits, so I need to provide some alternative
> handler.

Is "exotic fruits" a metaphor, or do you really mean that you want
the `read-buffer-to-switch' function to extend the completions with a
literal list of exotic fruit names?  What should `switch-to-buffer' do
in that case?

> Has this infrastructure been built into Emacs or is it exclusive to
> completion packages at this time?   If Emacs provides facilities for
> this kind of thing, what vocabulary should I become familiar with?

It would be helpful to clarify what infrastructure or functionality you
are talking about here, perhaps with an illustrative example.

-- 
Philip Kaludercic