Someone on the Fediverse asked if it’s possible to have Emacs visually highlight / flash the fragment of code that is currently evaluated in SuperCollider (via scel). It is! Here’s the code I use in my init.el to implement this, based on some example from some since-forgotten corner of the Net:

(defun undltd/sclang-highlight-defun (&optional silent-p)
  (cl-multiple-value-bind (beg end) (sclang-point-in-defun-p)
    (and beg end (pulse-momentary-highlight-region beg end))))

(defun undltd/sclang-highlight-region-or-line (&optional silent-p)
  (if (and transient-mark-mode mark-active)
      (pulse-momentary-highlight-region (region-beginning) (region-end))
    (pulse-momentary-highlight-one-line (point))))

(advice-add 'sclang-eval-defun :before #'undltd/sclang-highlight-defun)
(advice-add 'sclang-eval-region-or-line :before #'undltd/sclang-highlight-region-or-line)

(I tend to prefix all my custom functions with undltd/ to avoid potential name clashes with other libraries in the future).