Emacs: prevent cursor movement when scrolling off of the screen

Question

I am reviewing some code in emacs that has a series of for loops that span several pages. The indentations done by the author are poor so it is not easy to tell where loops begi

Answer 1

Here is a modification of https://github.com/nschum/highlight-parentheses.el/blob/master/highlight-parentheses.el, which will permit you to scroll up or down without deleting the overlays. You can add additional this-command statements to suit your needs.

(defun hl-paren-highlight ()
  "Highlight the parentheses around point."
  (unless
      (or
        (eq this-command 'mwheel-scroll)
        (eq this-command 'scroll-up)
        (eq this-command 'scroll-down))
    (unless (= (point) hl-paren-last-point)
      (setq hl-paren-last-point (point))
      (let ((overlays hl-paren-overlays)
            pos1 pos2
            (pos (point)))
        (save-excursion
          (condition-case err
              (while (and (setq pos1 (cadr (syntax-ppss pos1)))
                          (cdr overlays))
                (move-overlay (pop overlays) pos1 (1+ pos1))
                (when (setq pos2 (scan-sexps pos1 1))
                  (move-overlay (pop overlays) (1- pos2) pos2)
                  ))
            (error nil))
          (goto-char pos))
        (dolist (ov overlays)
          (move-overlay ov 1 1))))))