dotemacs

My Emacs configuration
git clone git://git.entf.net/dotemacs
Log | Files | Refs | LICENSE

README.org (27007B)


      1 #+title: corfu.el - Completion Overlay Region FUnction
      2 #+author: Daniel Mendler
      3 #+language: en
      4 #+export_file_name: corfu.texi
      5 #+texinfo_dir_category: Emacs misc features
      6 #+texinfo_dir_title: Corfu: (corfu).
      7 #+texinfo_dir_desc: Completion Overlay Region FUnction
      8 
      9 #+html: <a href="https://www.gnu.org/software/emacs/"><img alt="GNU Emacs" src="https://github.com/minad/corfu/blob/screenshots/emacs.svg?raw=true"/></a>
     10 #+html: <a href="http://elpa.gnu.org/packages/corfu.html"><img alt="GNU ELPA" src="https://elpa.gnu.org/packages/corfu.svg"/></a>
     11 #+html: <a href="http://elpa.gnu.org/devel/corfu.html"><img alt="GNU-devel ELPA" src="https://elpa.gnu.org/devel/corfu.svg"/></a>
     12 
     13 Corfu enhances completion at point with a small completion popup. The current
     14 candidates are shown in a popup below or above the point. Corfu is the
     15 minimalistic ~completion-in-region~ counterpart of the [[https://github.com/minad/vertico][Vertico]] minibuffer UI.
     16 
     17 Corfu is a small package, which relies on the Emacs completion facilities and
     18 concentrates on providing a polished completion UI. Completions are either
     19 provided by commands like ~dabbrev-completion~ or by pluggable backends
     20 (~completion-at-point-functions~, Capfs). Most programming language major modes
     21 implement a Capf. Furthermore the language server packages, [[https://github.com/joaotavora/eglot][Eglot]] and [[https://github.com/emacs-lsp/lsp-mode][Lsp-mode]],
     22 use Capfs which talk to the LSP server to retrieve the completions. Corfu does
     23 not include its own completion backends. The Emacs built-in Capfs and the Capfs
     24 provided by other programming language packages are usually sufficient. A few
     25 additional Capfs and completion utilities are provided by the [[https://github.com/minad/cape][Cape]] package.
     26 
     27 *NOTE*: Corfu uses child frames to show the popup and falls back to the default
     28 setting of the ~completion-in-region-function~ on non-graphical displays. If you
     29 want to use Corfu in the terminal, install the package [[https://codeberg.org/akib/emacs-corfu-terminal][corfu-terminal]], which
     30 provides an alternative overlay-based display.
     31 
     32 #+html: <img src="https://github.com/minad/corfu/blob/screenshots/light.png?raw=true">
     33 
     34 #+html: <img src="https://github.com/minad/corfu/blob/screenshots/dark.png?raw=true">
     35 
     36 #+toc: headlines 8
     37 
     38 * Features
     39 
     40 - Timer-based auto-completions (/off/ by default, set ~corfu-auto~).
     41 - Popup display with scrollbar indicator and arrow key navigation.
     42 - The popup can be summoned explicitly by pressing =TAB= at any time.
     43 - The current candidate is inserted with =TAB= and selected with =RET=.
     44 - Candidates sorting by prefix, string length and alphabetically.
     45 - The selected candidate is previewed (configurable via ~corfu-preview-current~).
     46 - The selected candidate automatically committed on further input by default.
     47   (configurable via ~corfu-preview-current~).
     48 - The [[https://github.com/oantolin/orderless][Orderless]] completion style is supported. The filter string can contain
     49   arbitrary characters, after inserting a space via =M-SPC= (configurable via
     50   ~corfu-quit-at-boundary~ and ~corfu-separator~).
     51 - Deferred completion style highlighting for performance.
     52 - Support for candidate annotations and documentation in the echo area.
     53 - Deprecated candidates are crossed out in the display.
     54 - Icons can be provided by an external package via margin formatter functions.
     55 - Extensions: Quick keys, Index keys, Sorting by history, Candidate documentation
     56 
     57 * Installation and Configuration
     58 
     59 Corfu is available from [[http://elpa.gnu.org/packages/corfu.html][GNU ELPA]], such that it can be installed directly via
     60 ~package-install~. After installation, the global minor mode can be enabled with
     61 =M-x global-corfu-mode=. In order to configure Corfu and other packages in your
     62 init.el, you may want to use ~use-package~.
     63 
     64 Corfu is highly flexible and customizable via ~corfu-*~ customization variables,
     65 such that you can adapt it precisely to your requirements. However in order to
     66 quickly try out the Corfu completion package, it should be sufficient to
     67 activate ~global-corfu-mode~. You can experiment with manual completion for
     68 example in an Elisp buffer or in an Eshell or Shell buffer. For auto completion,
     69 set ~corfu-auto=t~ before turning on ~global-corfu-mode~.
     70 
     71 Here is an example configuration:
     72 
     73 #+begin_src emacs-lisp
     74   (use-package corfu
     75     ;; Optional customizations
     76     ;; :custom
     77     ;; (corfu-cycle t)                ;; Enable cycling for `corfu-next/previous'
     78     ;; (corfu-auto t)                 ;; Enable auto completion
     79     ;; (corfu-separator ?\s)          ;; Orderless field separator
     80     ;; (corfu-quit-at-boundary nil)   ;; Never quit at completion boundary
     81     ;; (corfu-quit-no-match nil)      ;; Never quit, even if there is no match
     82     ;; (corfu-preview-current nil)    ;; Disable current candidate preview
     83     ;; (corfu-preselect-first nil)    ;; Disable candidate preselection
     84     ;; (corfu-on-exact-match nil)     ;; Configure handling of exact matches
     85     ;; (corfu-echo-documentation nil) ;; Disable documentation in the echo area
     86     ;; (corfu-scroll-margin 5)        ;; Use scroll margin
     87 
     88     ;; Enable Corfu only for certain modes.
     89     ;; :hook ((prog-mode . corfu-mode)
     90     ;;        (shell-mode . corfu-mode)
     91     ;;        (eshell-mode . corfu-mode))
     92 
     93     ;; Recommended: Enable Corfu globally.
     94     ;; This is recommended since Dabbrev can be used globally (M-/).
     95     ;; See also `corfu-excluded-modes'.
     96     :init
     97     (global-corfu-mode))
     98 
     99   ;; A few more useful configurations...
    100   (use-package emacs
    101     :init
    102     ;; TAB cycle if there are only few candidates
    103     (setq completion-cycle-threshold 3)
    104 
    105     ;; Emacs 28: Hide commands in M-x which do not apply to the current mode.
    106     ;; Corfu commands are hidden, since they are not supposed to be used via M-x.
    107     ;; (setq read-extended-command-predicate
    108     ;;       #'command-completion-default-include-p)
    109 
    110     ;; Enable indentation+completion using the TAB key.
    111     ;; `completion-at-point' is often bound to M-TAB.
    112     (setq tab-always-indent 'complete))
    113 #+end_src
    114 
    115 Dabbrev completion is based on =completion-in-region= and can be used with Corfu.
    116 You may want to swap the =dabbrev-completion= with the =dabbrev-expand= key for
    117 easier access, if you prefer completion. Also take a look at the =cape-dabbrev=
    118 completion at point function provided by my [[https://github.com/minad/cape][Cape]] package.
    119 
    120 #+begin_src emacs-lisp
    121   ;; Use Dabbrev with Corfu!
    122   (use-package dabbrev
    123     ;; Swap M-/ and C-M-/
    124     :bind (("M-/" . dabbrev-completion)
    125            ("C-M-/" . dabbrev-expand))
    126     ;; Other useful Dabbrev configurations.
    127     :custom
    128     (dabbrev-ignored-buffer-regexps '("\\.\\(?:pdf\\|jpe?g\\|png\\)\\'")))
    129 #+end_src
    130 
    131 If you start to configure the package more deeply, I recommend to give the
    132 Orderless completion style a try for filtering. Orderless completion is
    133 different from the familiar prefix TAB completion. Corfu can be used with the
    134 default completion styles. The use of Orderless is not a necessity.
    135 
    136 #+begin_src emacs-lisp
    137   ;; Optionally use the `orderless' completion style.
    138   (use-package orderless
    139     :init
    140     ;; Configure a custom style dispatcher (see the Consult wiki)
    141     ;; (setq orderless-style-dispatchers '(+orderless-dispatch)
    142     ;;       orderless-component-separator #'orderless-escapable-split-on-space)
    143     (setq completion-styles '(orderless basic)
    144           completion-category-defaults nil
    145           completion-category-overrides '((file (styles . (partial-completion))))))
    146 #+end_src
    147 
    148 The =basic= completion style is specified as fallback in addition to =orderless= in
    149 order to ensure that completion commands which rely on dynamic completion
    150 tables, e.g., ~completion-table-dynamic~ or ~completion-table-in-turn~, work
    151 correctly. See =+orderless-dispatch= in the [[https://github.com/minad/consult/wiki][Consult wiki]] for an advanced Orderless
    152 style dispatcher. Additionally enable =partial-completion= for file path
    153 expansion. =partial-completion= is important for file wildcard support. Multiple
    154 files can be opened at once with =find-file= if you enter a wildcard. You may also
    155 give the =initials= completion style a try.
    156 
    157 See also the [[https://github.com/minad/corfu/wiki][Corfu Wiki]] and the [[https://github.com/minad/cape][Cape manual]] for additional Capf configuration
    158 tips. The Lsp-mode configuration is documented in the wiki. For more general
    159 documentation read the chapter about completion in the [[https://www.gnu.org/software/emacs/manual/html_node/emacs/Completion.html][Emacs manual]]. If you want
    160 to create your own Capfs, you can find documentation about completion in the
    161 [[https://www.gnu.org/software/emacs/manual/html_node/elisp/Completion.html][Elisp manual]].
    162 
    163 ** Auto completion
    164 
    165 Auto completion is disabled by default, but can be enabled by setting
    166 ~corfu-auto=t~. Furthermore you may want to configure Corfu to quit completion
    167 eagerly, such that the completion popup stays out of your way when it appeared
    168 unexpectedly.
    169 
    170 #+begin_src emacs-lisp
    171   ;; Enable auto completion and configure quitting
    172   (setq corfu-auto t
    173         corfu-quit-no-match 'separator) ;; or t
    174 #+end_src
    175 
    176 I recommend to experiment a bit with the various settings and key bindings to
    177 find a configuration which works for you. There is no one size fits all
    178 solution. Some people like auto completion, some like manual completion, some
    179 want to cycle with TAB and some with the arrow keys.
    180 
    181 In case you like aggressive auto completion settings, where the completion popup
    182 appears immediately, I recommend to use a cheap completion style like =basic=,
    183 which performs prefix filtering. In this case Corfu completion should still be
    184 very fast in buffers with efficient completion backends. You can try the
    185 following settings in an Elisp buffer or the Emacs scratch buffer.
    186 
    187 #+begin_src emacs-lisp
    188   ;; Aggressive completion, cheap prefix filtering.
    189   (setq-local corfu-auto t
    190               corfu-auto-delay 0
    191               corfu-auto-prefix 0
    192               completion-styles '(basic))
    193 #+end_src
    194 
    195 If you want to combine fast prefix filtering and Orderless filtering you can
    196 still do that by defining a custom Orderless completion style via
    197 =orderless-define-completion-style=. We use a custom style dispatcher, which
    198 enables prefix filtering for input shorter than 4 characters. Note that such a
    199 setup is quite advanced. Please refer to the Orderless documentation and source
    200 code for further details.
    201 
    202 #+begin_src emacs-lisp
    203   (defun orderless-fast-dispatch (word index total)
    204     (and (= index 0) (= total 1) (length< word 4)
    205          `(orderless-regexp . ,(concat "^" (regexp-quote word)))))
    206 
    207   (orderless-define-completion-style orderless-fast
    208     (orderless-style-dispatchers '(orderless-fast-dispatch))
    209     (orderless-matching-styles '(orderless-literal orderless-regexp)))
    210 
    211   (setq-local corfu-auto t
    212               corfu-auto-delay 0
    213               corfu-auto-prefix 0
    214               completion-styles '(orderless-fast))
    215 #+end_src
    216 
    217 ** Completing in the minibuffer
    218 
    219 Corfu can be used for completion in the minibuffer, since it relies on child
    220 frames to display the candidates. By default, ~global-corfu-mode~ does not
    221 activate ~corfu-mode~ in the minibuffer, to avoid interference with specialised
    222 minibuffer completion UIs like Vertico or Mct. However you may still want to
    223 enable Corfu completion for commands like ~M-:~ (~eval-expression~) or ~M-!~
    224 (~shell-command~), which read from the minibuffer. Activate ~corfu-mode~ only if
    225 ~completion-at-point~ is bound in the minibuffer-local keymap to achieve this
    226 effect.
    227 
    228 #+begin_src emacs-lisp
    229   (defun corfu-enable-in-minibuffer ()
    230     "Enable Corfu in the minibuffer if `completion-at-point' is bound."
    231     (when (where-is-internal #'completion-at-point (list (current-local-map)))
    232       ;; (setq-local corfu-auto nil) Enable/disable auto completion
    233       (corfu-mode 1)))
    234   (add-hook 'minibuffer-setup-hook #'corfu-enable-in-minibuffer)
    235 #+end_src
    236 
    237 You can also enable Corfu more generally for every minibuffer, as long as no
    238 other completion UI is active. If you use Mct or Vertico as your main minibuffer
    239 completion UI, the following snippet should yield the desired result.
    240 
    241 #+begin_src emacs-lisp
    242   (defun corfu-enable-always-in-minibuffer ()
    243     "Enable Corfu in the minibuffer if Vertico/Mct are not active."
    244     (unless (or (bound-and-true-p mct--active)
    245                 (bound-and-true-p vertico--input))
    246       ;; (setq-local corfu-auto nil) Enable/disable auto completion
    247       (corfu-mode 1)))
    248   (add-hook 'minibuffer-setup-hook #'corfu-enable-always-in-minibuffer 1)
    249 #+end_src
    250 
    251 ** Completing in the Eshell or Shell
    252 
    253 When completing in the Eshell I recommend conservative local settings without
    254 auto completion, such that the completion behavior is similar to widely used
    255 shells like Bash, Zsh or Fish.
    256 
    257 #+begin_src emacs-lisp
    258   (add-hook 'eshell-mode-hook
    259             (lambda ()
    260               (setq-local corfu-auto nil)
    261               (corfu-mode)))
    262 #+end_src
    263 
    264 When pressing =RET= while the Corfu popup is visible, the ~corfu-insert~ command
    265 will be invoked. This command does inserts the currently selected candidate, but
    266 it does not send the prompt input to Eshell or the comint process. Therefore you
    267 often have to press =RET= twice which feels like an unnecessary double
    268 confirmation. Fortunately it is easy to improve this! In my configuration I
    269 define the advice ~corfu-send-shell~ which sends the candidate after insertion.
    270 
    271 #+begin_src emacs-lisp
    272   (defun corfu-send-shell (&rest _)
    273     "Send completion candidate when inside comint/eshell."
    274     (cond
    275      ((and (derived-mode-p 'eshell-mode) (fboundp 'eshell-send-input))
    276       (eshell-send-input))
    277      ((and (derived-mode-p 'comint-mode)  (fboundp 'comint-send-input))
    278       (comint-send-input))))
    279 
    280   (advice-add #'corfu-insert :after #'corfu-send-shell)
    281 #+end_src
    282 
    283 Shell completion uses the flexible ~Pcomplete~ mechanism internally, which allows
    284 you to program the completions per shell command. If you want to know more, look
    285 into this [[https://www.masteringemacs.org/article/pcomplete-context-sensitive-completion-emacs][blog post]], which shows how to configure Pcomplete for git commands. I
    286 recommend the [[https://github.com/JonWaltman/pcmpl-args.el][pcmpl-args]] package which extends Pcomplete with completion support
    287 and helpful annotation support for more commands. Similar to the Fish shell,
    288 pcmpl-args uses man page parsing and --help output parsing to dynamically
    289 generate completions. This package brings Eshell completion to another level!
    290 
    291 Unfortunately Pcomplete has a few technical issues, which we can work around
    292 with the [[https://github.com/minad/cape][Cape]] library (Completion at point extensions). Cape provides wrappers,
    293 which sanitize the Pcomplete function. Ideally the bugs in Pcomplete should be
    294 fixed upstream. *For now these two advices are strongly recommended to achieve a
    295 sane Eshell experience.*
    296 
    297 #+begin_src emacs-lisp
    298   ;; Silence the pcomplete capf, no errors or messages!
    299   (advice-add 'pcomplete-completions-at-point :around #'cape-wrap-silent)
    300 
    301   ;; Ensure that pcomplete does not write to the buffer
    302   ;; and behaves as a pure `completion-at-point-function'.
    303   (advice-add 'pcomplete-completions-at-point :around #'cape-wrap-purify)
    304 #+end_src
    305 
    306 ** Orderless completion
    307 
    308 [[https://github.com/oantolin/orderless][Orderless]] is an advanced completion style that supports multi-component search
    309 filters separated by a configurable character (space, by default). Normally,
    310 entering characters like space which lie outside the completion region
    311 boundaries (words, typically) causes Corfu to quit. This behavior is helpful
    312 with auto-completion, which may pop-up when not desired, e.g. on entering a new
    313 variable name. Just keep typing and Corfu will get out of the way.
    314 
    315 But orderless search terms can contain arbitrary characters; they are also
    316 interpreted as regular expressions. To use orderless, set ~corfu-separator~ (a
    317 space, by default) to the primary character of your orderless component
    318 separator.
    319 
    320 Then, when a new orderless component is desired, use =M-SPC=
    321 (~corfu-insert-separator~) to enter the /first/ component separator in the input,
    322 and arbitrary orderless search terms and new separators can be entered
    323 thereafter.
    324 
    325 To treat the entire input as Orderless input, you can set the customization
    326 option ~corfu-quit-at-boundary=t~. This disables the predicate which checks if the
    327 current completion boundary has been left. In contrast, if you /always/ want to
    328 quit at the boundary, simply set ~corfu-quit-at-boundary=nil~. By default
    329 ~corfu-quit-at-boundary~ is set to ~separator~ which quits at completion boundaries
    330 as long as no separator has been inserted with ~corfu-insert-separator~.
    331 
    332 Finally, there exists the user option ~corfu-quit-no-match~ which is set to
    333 =separator= by default. With this setting Corfu stays alive as soon as you start
    334 advanced filtering with a ~corfu-separator~ even if there are no matches, for
    335 example due to a typo. As long as no separator character has been inserted with
    336 ~corfu-insert-separator~, Corfu will still quit if there are no matches. This
    337 ensures that the Corfu popup goes away quickly if completion is not possible.
    338 
    339 In the following we show two configurations, one which works best with auto
    340 completion and one which may work better with manual completion if you prefer to
    341 always use =SPC= to separate the Orderless components.
    342 
    343  #+begin_src emacs-lisp
    344    ;; Auto completion example
    345    (use-package corfu
    346      :custom
    347      (corfu-auto t)          ;; Enable auto completion
    348      ;; (corfu-separator ?_) ;; Set to orderless separator, if not using space
    349      :bind
    350      ;; Another key binding can be used, such as S-SPC.
    351      ;; (:map corfu-map ("M-SPC" . corfu-insert-separator))
    352      :init
    353      (global-corfu-mode))
    354 
    355    ;; Manual completion example
    356    (use-package corfu
    357      :custom
    358      ;; (corfu-separator ?_) ;; Set to orderless separator, if not using space
    359      :bind
    360      ;; Configure SPC for separator insertion
    361      (:map corfu-map ("SPC" . corfu-insert-separator))
    362      :init
    363      (global-corfu-mode))
    364 #+end_src
    365 
    366 ** TAB-and-Go completion
    367 
    368 You may be interested in configuring Corfu in TAB-and-Go style. Pressing TAB
    369 moves to the next candidate and further input will then commit the selection.
    370 Note that further input will not expand snippets or templates, which may not be
    371 desired but which leads overall to a more predictable behavior. In order to
    372 force snippet expansion, confirm a candidate explicitly with ~RET~.
    373 
    374 #+begin_src emacs-lisp
    375   (use-package corfu
    376     ;; TAB-and-Go customizations
    377     :custom
    378     (corfu-cycle t)             ;; Enable cycling for `corfu-next/previous'
    379     (corfu-preselect-first nil) ;; Disable candidate preselection
    380 
    381     ;; Use TAB for cycling, default is `corfu-complete'.
    382     :bind
    383     (:map corfu-map
    384           ("TAB" . corfu-next)
    385           ([tab] . corfu-next)
    386           ("S-TAB" . corfu-previous)
    387           ([backtab] . corfu-previous))
    388 
    389     :init
    390     (global-corfu-mode))
    391 #+end_src
    392 
    393 ** Transfer completion to the minibuffer
    394 
    395 Sometimes it is useful to transfer the Corfu completion session to the
    396 minibuffer, since the minibuffer offers richer interaction features. In
    397 particular, [[https://github.com/oantolin/embark][Embark]] is available in the minibuffer, such that you can act on the
    398 candidates or export/collect the candidates to a separate buffer. Hopefully we
    399 can also add Corfu-support to Embark in the future, such that at least
    400 export/collect is possible directly from Corfu. But in my opinion having the
    401 ability to transfer the Corfu completion to the minibuffer is an even better
    402 feature, since further completion can be performed there.
    403 
    404 The command ~corfu-move-to-minibuffer~ is defined here in terms of
    405 ~consult-completion-in-region~, which uses the minibuffer completion UI via
    406 ~completing-read~.
    407 
    408 #+begin_src emacs-lisp
    409   (defun corfu-move-to-minibuffer ()
    410     (interactive)
    411     (let ((completion-extra-properties corfu--extra)
    412           completion-cycle-threshold completion-cycling)
    413       (apply #'consult-completion-in-region completion-in-region--data)))
    414   (define-key corfu-map "\M-m" #'corfu-move-to-minibuffer)
    415 #+end_src
    416 
    417 * Key bindings
    418 
    419 Corfu uses a transient keymap ~corfu-map~ which is active while the popup is
    420 shown. The keymap defines the following remappings and bindings:
    421 
    422 - ~beginning-of-buffer~ -> ~corfu-first~
    423 - ~end-of-buffer~ -> ~corfu-last~
    424 - ~scroll-down-command~ -> ~corfu-scroll-down~
    425 - ~scroll-up-command~ -> ~corfu-scroll-up~
    426 - ~next-line~, =down=, =M-n= -> ~corfu-next~
    427 - ~previous-line~, =up=, =M-p= -> ~corfu-previous~
    428 - ~completion-at-point~, =TAB= -> ~corfu-complete~
    429 - =RET= -> ~corfu-insert~
    430 - =M-g= -> ~corfu-info-location~
    431 - =M-h= -> ~corfu-info-documentation~
    432 - =M-SPC= -> ~corfu-insert-separator~
    433 - =C-g= -> ~corfu-quit~
    434 - ~keyboard-escape-quit~ -> ~corfu-reset~
    435 
    436 * Extensions
    437 :properties:
    438 :custom_id: extensions
    439 :end:
    440 
    441 We maintain small extension packages to Corfu in this repository in the
    442 subdirectory [[https://github.com/minad/corfu/tree/main/extensions][extensions/]]. The extensions are installed together with Corfu if
    443 you pull the package from ELPA. The extensions are inactive by default and can
    444 be enabled manually if desired. Furthermore it is possible to install all of the
    445 files separately, both ~corfu.el~ and the ~corfu-*.el~ extensions. Currently the
    446 following extensions come with the Corfu ELPA package:
    447 
    448 - [[https://github.com/minad/corfu/blob/main/extensions/corfu-history.el][corfu-history]]: =corfu-history-mode= to remember selected candidates and to improve sorting.
    449 - [[https://github.com/minad/corfu/blob/main/extensions/corfu-indexed.el][corfu-indexed]]: =corfu-indexed-mode= to select indexed candidates with prefix arguments.
    450 - [[https://github.com/minad/corfu/blob/main/extensions/corfu-info.el][corfu-info]]: Actions to access the candidate location and documentation.
    451 - [[https://github.com/minad/corfu/blob/main/extensions/corfu-quick.el][corfu-quick]]: Commands to select using Avy-style quick keys.
    452 
    453 See the Commentary of those files for configuration details.
    454 
    455 * Complementary packages
    456 
    457 Corfu works well together with all packages providing code completion via the
    458 ~completion-at-point-functions~. Many modes and packages already provide a Capf
    459 out of the box. Nevertheless you may want to look into complementary packages to
    460 enhance your setup.
    461 
    462 - [[https://codeberg.org/akib/emacs-corfu-terminal][corfu-terminal]]: The corfu-terminal package provides an overlay-based display
    463   for Corfu, such that you can use Corfu in terminal Emacs.
    464 
    465 - [[https://github.com/galeo/corfu-doc][corfu-doc]]: The corfu-doc package displays the candidate documentation in a
    466   popup next to the Corfu popup, similar to =company-quickhelp=.
    467 
    468 - [[https://github.com/oantolin/orderless][Orderless]]: Corfu supports completion styles, including the advanced
    469   [[https://github.com/oantolin/orderless][Orderless]] completion style, where the filtering expressions are separated by
    470   spaces or another character (see ~corfu-separator~).
    471 
    472 - [[https://github.com/minad/cape][Cape]]: Additional Capf backends and =completion-in-region= commands
    473   are provided by the [[https://github.com/minad/cape][Cape]] package. Among others, the package supplies a file
    474   path and a Dabbrev completion backend. Cape provides the ~cape-company-to-capf~
    475   adapter to reuse Company backends in Corfu. Furthermore the function
    476   ~cape-super-capf~ can merge multiple Capfs, such that the candidates of multiple
    477   Capfs are displayed together at the same time.
    478 
    479 - [[https://github.com/jdtsmith/kind-icon][kind-icon]]: Icons are supported by Corfu via an external package. For example
    480   the [[https://github.com/jdtsmith/kind-icon][kind-icon]] package provides beautifully styled SVG icons based on
    481   monochromatic icon sets like material design.
    482 
    483 - [[https://github.com/JonWaltman/pcmpl-args.el][pcmpl-args]]: Extend the Eshell/Shell Pcomplete mechanism with support for many
    484   more commands. Similar to the Fish shell, Pcomplete uses man page parsing to
    485   dynamically retrieve the completions and helpful annotations. This package
    486   brings Eshell completions to another level!
    487 
    488 - [[https://github.com/minad/tempel][Tempel]]: Tiny template/snippet package with templates in Lisp syntax, which
    489   can be used in conjunction with Corfu.
    490 
    491 - [[https://github.com/minad/vertico][Vertico]]: You may also want to look into my [[https://github.com/minad/vertico][Vertico]] package. Vertico is the
    492   minibuffer completion counterpart of Corfu.
    493 
    494 * Alternatives
    495 
    496 - [[https://github.com/company-mode/company-mode][Company]]: Company is a widely used and mature completion package, which
    497   implements a similar interaction model and popup UI as Corfu. While Corfu
    498   relies exclusively on the standard Emacs completion API (Capfs), Company
    499   defines its own API for the backends. Company includes its completion
    500   backends, which are incompatible with the Emacs completion infrastructure. As
    501   a result of this design, Company is a more complex package than Corfu. Company
    502   by default uses overlays for the popup in contrast to the child frames used by
    503   Corfu. Overall both packages work well, but Company integrates less tightly
    504   with Emacs. The ~completion-styles~ support is more limited and the
    505   ~completion-at-point~ command and the ~completion-in-region~ function do not
    506   invoke Company.
    507 
    508 - [[https://git.sr.ht/~protesilaos/mct][Mct]]: Protesilaos' Minibuffer Confines Transcended package supports both
    509   minibuffer completion and completion in region. It reuses the default
    510   completion UI for this purpose and installs a timer which live updates the
    511   completion buffer. The main advantage of Mct is that you work with a regular
    512   Emacs buffer instead of with a popup. You can take advantage of the usual
    513   Emacs commands to navigate in the completions buffer. On top, Mct enhances the
    514   movement such that you can quickly switch between the completions buffer and
    515   the minibuffer or the region which is being completed. Mct does not support
    516   timer-based auto completion, but the integration into Emacs is naturally
    517   tight. Note that Mct development is currently [[https://protesilaos.com/codelog/2022-04-14-emacs-discontinue-mct/][discontinued]] due to recent
    518   changes of the default completion UI on the Emacs master branch.
    519 
    520 - [[https://github.com/minad/consult][consult-completion-in-region]]: The Consult package provides the function
    521   ~consult-completion-in-region~ which can be set as ~completion-in-region-function~
    522   such that it handles ~completion-at-point~. The function works by transferring
    523   the in-buffer completion to the minibuffer. In the minibuffer, the minibuffer
    524   completion UI, for example [[https://github.com/minad/vertico][Vertico]] takes over. If you prefer to perform all
    525   your completions in the minibuffer ~consult-completion-in-region~ is your best
    526   option.
    527 
    528 * Contributions
    529 
    530 Since this package is part of [[http://elpa.gnu.org/packages/corfu.html][GNU ELPA]] contributions require a copyright
    531 assignment to the FSF.