Markdown has multiple types of lists, and in my mind checking items from those list means different things depending on the type.

- [ ] this item is open
- [x] this item is close
- this item is also open
- ~~this item is also close~~

For checklists I want the box to be checked when I toggle the item for, others I want the item to be crossed out via strike-through. All of those actions already exist in Emacs Markdown-Mode, but they are different depending on the list, I want Emacs to do what I mean no matter the list so I added this

(defun coder--markdown-toogle-list-item-dwim ()
    "Toogle the current list item depending on the type do the right thing.

1. When it is not a markdown list, ignore
2. When the list is a checklist indicated by [ ] check the checkbox
3. When the list is a normal list, strike-through the current item
4. When the item already has strike-through applied, un-strike it"
    (interactive)
    (save-match-data
      (save-excursion
        (when-let ((bounds (markdown-cur-list-item-bounds)))
          ;; move to the beginning of the item after the list marker
          (goto-char (cl-first bounds))
          (forward-char (cl-fourth bounds))

          (cond ((looking-at "\\[[\s-xX]\\]") (markdown-toggle-gfm-checkbox))
                ((thing-at-point-looking-at markdown-regex-strike-through) (markdown-insert-strike-through))
                (t (progn
                     (set-mark (point))
                     (end-of-line)
                     (activate-mark)
                     ;; remove trailing whitespace from line first, this
                     ;; otherwise breaks strikethrough rendering
                     (delete-trailing-whitespace)
                     (markdown-insert-strike-through))))))))

Happy markdown editing!