docs(corfu): simplify and show how to add capfs

modules/completion/corfu/README.org

@@ -128,6 +128,19 @@ A few variables may be set to change behavior of this module:
 - [[var:+corfu-icon-mapping]] ::
   Configures icons used for each completion. See its documentation for details.
 
+** Adding CAPFs to a mode
+To add other CAPFs on a mode-per-mode basis, put either of the following in your
+~config.el~:
+
+#+begin_src emacs-lisp
+(add-hook! some-mode (add-to-list 'completion-at-point-functions #'some-capf))
+;; OR, but note the different call signature
+(add-hook 'some-mode-hook (lambda () (add-to-list 'completion-at-point-functions #'some-capf)))
+#+end_src
+
+Also see ~add-hook!~'s documentation for additional ways to call it.
+~add-hook~ only accepts the quoted arguments form above.
+
 * Troubleshooting
 [[doom-report:][Report an issue?]]
 

modules/completion/corfu/config.el

@@ -153,14 +153,11 @@ Meant as :around advice for `corfu--recompute'."
     (map! :map 'corfu-map "s-<down>" #'corfu-move-to-minibuffer
           (:when (modulep! :editor evil) "s-j" #'corfu-move-to-minibuffer))))
 
-(defmacro +corfu--add-capf! (capf)
-  "Create sexp to add CAPF to the list of CAPFs."
-  `(add-to-list 'completion-at-point-functions ,capf))
 (use-package! cape
   :after corfu
   :config
-  (add-hook! prog-mode (+corfu--add-capf! #'cape-file))
-  (add-hook! (org-mode markdown-mode) (+corfu--add-capf! #'cape-elisp-block))
+  (add-hook! prog-mode (add-to-list 'completion-at-point-functions #'cape-file))
+  (add-hook! (org-mode markdown-mode) (add-to-list 'completion-at-point-functions #'cape-elisp-block))
   (advice-add #'lsp-completion-at-point :around #'cape-wrap-noninterruptible))
 
 (use-package! yasnippet-capf