org-toggle-emphasis: easily toggle emphasis markers: =~*/_+

org-toggle-emphasis.el

(defun my/org-toggle-emphasis (type)
    "Toggle org emphasis TYPE (a character) at point."
    (cl-labels ((in-emph (re)
		  "See if in org emphasis given by RE."
		  (and (org-in-regexp re 2)
		       (>= (point) (match-beginning 3))
		       (<= (point) (match-end 4))))
		(de-emphasize ()
		  "Remove most recently matched org emphasis markers."
		  (save-excursion
		    (replace-match "" nil nil nil 3)
		    (delete-region (match-end 4) (1+ (match-end 4))))))
      (let* ((res (vector org-emph-re org-verbatim-re))
	     (idx (cl-case type (?/ 0) (?* 0) (?_ 0) (?+ 0) (?= 1) (?~ 1)))
	     (re (aref res idx))
	     (other-re (aref res (- 1 idx)))
	     (type-re (string-replace (if (= idx 1) "=~" "*/_+")
				      (char-to-string type) re))
	     add-bounds offset is-word)
	(save-match-data
	  (if (region-active-p)
	      (if (in-emph type-re) (de-emphasize) (org-emphasize type))
	    (if (eq (char-before) type) (backward-char))
	    (if (in-emph type-re)	;nothing marked, in emph text?
		(de-emphasize)
	      (setq add-bounds		; check other flavors
		    (if (or (in-emph re) (in-emph other-re))
			(cons (match-beginning 4) (match-end 4))
		      (setq is-word t)
		      (bounds-of-thing-at-point 'symbol))))
	    (if add-bounds
		(let ((off (- (point) (car add-bounds)))
		      (at-end (= (point) (cdr add-bounds))))
		  (set-mark (car add-bounds))
		  (goto-char (cdr add-bounds))
		  (org-emphasize type)	;deletes marked region!
		  (unless is-word	; delete extra spaces
		    (goto-char (car add-bounds))
		    (when (eq (char-after) ?\s) (delete-char 1))
		    (goto-char (+ 2 (cdr add-bounds)))
		    (when (eq (char-after) ?\s) (delete-char 1)))
		  (goto-char (+ (car add-bounds) off
				(cond ((= off 0) 0) (at-end 2) (t 1)))))
	      (if is-word (org-emphasize type))))))))

Just tweaked to correctly de-emphasize right after an emphasized word *word*[s-b] -> word, and to leave point outside the word if point is on the boundary to begin with.

I had in fact wanted this, and reached for current-word, which does the right thing

Interesting, I thought current-word 'word etc. all used the same underlying syntax tables to define a word. Guess not! Thanks for that.