1 files changed, 61 insertions, 0 deletions
diff --git a/users/aspen/emacs.d/show-matching-paren.el b/users/aspen/emacs.d/show-matching-paren.el
new file mode 100644
index 000000000000..ab65a912a8d1
--- /dev/null
+++ b/users/aspen/emacs.d/show-matching-paren.el
@@ -0,0 +1,61 @@
+;;; -*- lexical-binding: t; -*-
+
+;;; https://with-emacs.com/posts/ui-hacks/show-matching-lines-when-parentheses-go-off-screen/
+
+;; we will call `blink-matching-open` ourselves...
+(remove-hook 'post-self-insert-hook
+             #'blink-paren-post-self-insert-function)
+;; this still needs to be set for `blink-matching-open` to work
+(setq blink-matching-paren 'show)
+
+(let ((ov nil)) ; keep track of the overlay
+  (advice-add
+   #'show-paren-function
+   :after
+    (defun show-paren--off-screen+ (&rest _args)
+      "Display matching line for off-screen paren."
+      (when (overlayp ov)
+        (delete-overlay ov))
+      ;; check if it's appropriate to show match info,
+      ;; see `blink-paren-post-self-insert-function'
+      (when (and (overlay-buffer show-paren--overlay)
+                 (not (or cursor-in-echo-area
+                          executing-kbd-macro
+                          noninteractive
+                          (minibufferp)
+                          this-command))
+                 (and (not (bobp))
+                      (memq (char-syntax (char-before)) '(?\) ?\$)))
+                 (= 1 (logand 1 (- (point)
+                                   (save-excursion
+                                     (forward-char -1)
+                                     (skip-syntax-backward "/\\")
+                                     (point))))))
+        ;; rebind `minibuffer-message' called by
+        ;; `blink-matching-open' to handle the overlay display
+        (cl-letf (((symbol-function #'minibuffer-message)
+                   (lambda (msg &rest args)
+                     (let ((msg (apply #'format-message msg args)))
+                       (setq ov (display-line-overlay+
+                                 (window-start) msg ))))))
+          (blink-matching-open))))))
+
+(defun display-line-overlay+ (pos str &optional face)
+  "Display line at POS as STR with FACE.
+
+FACE defaults to inheriting from default and highlight."
+  (let ((ol (save-excursion
+              (goto-char pos)
+              (make-overlay (line-beginning-position)
+                            (line-end-position)))))
+    (overlay-put ol 'display str)
+    (overlay-put ol 'face
+                 (or face '(:inherit default :inherit highlight)))
+    ol))
+
+(setq show-paren-style 'paren
+      show-paren-delay 0.03
+      show-paren-highlight-openparen t
+      show-paren-when-point-inside-paren nil
+      show-paren-when-point-in-periphery t)
+(show-paren-mode 1)