[fu] init-highlight

modules/init-highlight.el

@@ -31,8 +31,6 @@
     (load (file-name-concat (locate-user-emacs-file "modules") "init-require"))))
 (exordium-require 'init-prefs)
 
-(require 'hi-lock)
-
 (use-package highlight
   :defer t)
 
@@ -45,15 +43,22 @@
 
 
 ;;; Highlight symbol under point automatically after a small delay.
-
 (when exordium-highlight-symbol
   (use-package highlight-symbol
+    ;; N.B. the `highlight-symbol' package has not been updated for a while (at
+    ;; the time of writing this comment in 2024 last update was from 2016) and
+    ;; it forcibly defines its own alias for `highlight-symbol-at-point',
+    ;; clobbering the one delivered with Emacs in `hi-lock'. However, the
+    ;; `highlight-symbol' implementation is nicer, as it allows to remove
+    ;; highlighting with the same keybinding. Also the `highlight-symbol-mode'
+    ;; is the mode that is turned on (`hi-lock-mode' is not turned on), so
+    ;; let's keep that implementation, by ensuring load order.
+    :after (hi-lock)
     :diminish highlight-symbol-mode
-    :hook (prog-mode . highlight-symbol-mode)
+    :hook ((prog-mode . highlight-symbol-mode)
+           (prog-mode . highlight-symbol-nav-mode))
     :custom
-    (highlight-symbol-on-navigation-p t)
-    :config
-    (highlight-symbol-nav-mode)))
+    (highlight-symbol-on-navigation-p t)))
 
 
 ;;; Highlight/unhighlight symbol under point using a key.
@@ -62,22 +67,29 @@
   "List of regexps for the currently highlighted symbols.
 This variable is buffer-local.")
 
-(defun exordium-highlight-symbol-at-point ()
-  "Toggle highlighting of occurrences of the symbol under point.
-Up to 4 different symbols can be highlighted using different
-colors at one time."
-  (interactive)
-  (let ((regex (find-tag-default-as-symbol-regexp)))
-    (cond ((member regex exordium-highlighted-symbols)
-           ;; Remove highlight for this symbol.
-           (setq exordium-highlighted-symbols (remove regex exordium-highlighted-symbols))
-           (hi-lock-unface-buffer regex))
-          (t
-           ;; Add highlight for this symbol.
-           (setq exordium-highlighted-symbols (cons regex exordium-highlighted-symbols))
-           (hi-lock-face-symbol-at-point)))))
-
-(global-set-key (kbd "C-c C-SPC") #'exordium-highlight-symbol-at-point)
+(use-package hi-lock
+  :ensure nil
+  :demand t
+  :autoload (hi-lock-regexp-okay)
+  :functions (exordium-highlight-symbol-at-point)
+  :init
+  (defun exordium-highlight-symbol-at-point ()
+    "Toggle highlighting of occurrences of the symbol under point.
+Faces from `hi-lock-face-defaults' are used to perform the highlight, so up
+to the number of elements in that list of different symbols can
+be highlighted using different colors at one time."
+    (interactive)
+    (when-let* ((regexp (ignore-errors (hi-lock-regexp-okay
+                                        (find-tag-default-as-symbol-regexp)))))
+      (cond ((member regexp exordium-highlighted-symbols)
+             ;; Remove highlight for this symbol.
+             (setq exordium-highlighted-symbols (remove regexp exordium-highlighted-symbols))
+             (hi-lock-unface-buffer regexp))
+            (t
+             ;; Add highlight for this symbol.
+             (setq exordium-highlighted-symbols (cons regexp exordium-highlighted-symbols))
+             (hi-lock-face-symbol-at-point)))))
+  :bind  ("C-c C-SPC" . #'exordium-highlight-symbol-at-point))
 
 
 ;; Highlight color name and Hex values in buffer.