GNU bug report logs - #47711
27.1; Deferred highlighting support in `completion-all-completions', `vertico--all-completions`

Previous Next

Full log

View this message in rfc822 format

From: help-debbugs <at> gnu.org (GNU bug Tracking System)
To: Daniel Mendler <mail <at> daniel-mendler.de>
Subject: bug#47711: closed (Re: bug#47711: 27.1; Deferred highlighting
 support in `completion-all-completions', `vertico--all-completions`)
Date: Fri, 29 Nov 2024 17:56:02 +0000

[Message part 1 (text/plain, inline)]

Your bug report

#47711: 27.1; Deferred highlighting support in `completion-all-completions', `vertico--all-completions`

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 47711 <at> debbugs.gnu.org.

-- 
47711: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=47711
GNU Bug Tracking System
Contact help-debbugs <at> gnu.org with problems

[Message part 2 (message/rfc822, inline)]

From: Daniel Mendler <mail <at> daniel-mendler.de>
To: 47711-done <at> debbugs.gnu.org
Subject: Re: bug#47711: 27.1; Deferred highlighting support in
 `completion-all-completions', `vertico--all-completions`
Date: Fri, 29 Nov 2024 18:52:45 +0100

Has been implemented via completion-lazy-hilit.

[Message part 3 (message/rfc822, inline)]

From: Daniel Mendler <mail <at> daniel-mendler.de>
To: bug-gnu-emacs <at> gnu.org
Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>
Subject: 27.1; Deferred highlighting support in `completion-all-completions',
 `vertico--all-completions`
Date: Sun, 11 Apr 2021 22:51:14 +0200

Emacs is lacking a possibility to defer the completion highlighting when
computing completions via `completion-all-completions'. This feature is
important for the performance of completion UIs when the set of all
completions is much larger than the set of completions which are
displayed.

The Vertico package defers highlighting by modifying the
`completion*-hilit-*' function with advices.

(declare-function orderless-highlight-matches "ext:orderless")
(defun vertico--all-completions (&rest args)
  "Compute all completions for ARGS with deferred highlighting."
  (cl-letf* ((orig-pcm (symbol-function 
#'completion-pcm--hilit-commonality))
             (orig-flex (symbol-function 
#'completion-flex-all-completions))
             ((symbol-function #'completion-flex-all-completions)
              (lambda (&rest args)
                ;; Unfortunately for flex we have to undo the deferred 
highlighting, since flex uses
                ;; the completion-score for sorting, which is applied 
during highlighting.
                (cl-letf (((symbol-function 
#'completion-pcm--hilit-commonality) orig-pcm))
                  (apply orig-flex args))))
             ;; Defer the following highlighting functions
             (hl #'identity)
             ((symbol-function #'completion-hilit-commonality)
              (lambda (cands prefix &optional base)
                (setq hl (lambda (x) (nconc 
(completion-hilit-commonality x prefix base) nil)))
                (and cands (nconc cands base))))
             ((symbol-function #'completion-pcm--hilit-commonality)
              (lambda (pattern cands)
                (setq hl (lambda (x) (completion-pcm--hilit-commonality 
pattern x)))
                cands))
             ((symbol-function #'orderless-highlight-matches)
              (lambda (pattern cands)
                (setq hl (lambda (x) (orderless-highlight-matches 
pattern x)))
                cands)))
    (cons (apply #'completion-all-completions args) hl)))

This function `vertico--all-completions` returns the list of completions 
and a highlighting
function which can then be used to highlight the completions on the fly.
It is a prototype of how some improved functionality in Emacs could look 
like.

(completion-all-completions STRING TABLE PRED POINT &optional METADATA 
DEFER-HL)

or

(completion-all-completions-defer-hl STRING TABLE PRED POINT &optional 
METADATA)

If DEFER-HL=t, then the function returns the completions and a
highlighting function. One may consider returning a triple of base,
completions and highlighting functions. Internally the completion styles
should be adapted such that they support the deferred highlighting.

It could be that this feature becomes less needed with the introduction
of gccemacs in the future.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.