gistfile1.txt

(defun ledger-move-transaction-up ()
  (interactive)
  (save-excursion
    (let* ((ext-A (ledger-navigate-find-element-extents (point)))
           (prev (ledger-navigate-prev-xact-or-directive))
           (ext-B (ledger-navigate-find-element-extents (point)))
           (start-A (car ext-A))
           (end-A (cadr ext-A))
           (start-B (car ext-B))
           (end-B (cadr ext-B))
           (xact-A (buffer-substring-no-properties start-A end-A))
           (xact-B (buffer-substring-no-properties start-B end-B))
           (sep (buffer-substring-no-properties end-B start-A)))
      (unless prev (user-error "Cannot move this transaction further up"))
      (delete-region start-B end-A)
      (insert (concat xact-A sep xact-B)))))

(defun ledger-move-transaction-down ()
  (interactive)
  (let* ((ext-A (ledger-navigate-find-element-extents (point)))
         (next (ledger-navigate-next-xact))
         (ext-B (ledger-navigate-find-element-extents (point)))
         (start-A (car ext-A))
         (end-A (cadr ext-A))
         (start-B (car ext-B))
         (end-B (cadr ext-B))
         (xact-A (buffer-substring-no-properties start-A end-A))
         (xact-B (buffer-substring-no-properties start-B end-B))
         (sep (buffer-substring-no-properties end-A start-B)))
    (delete-region start-A end-B)
    (insert (concat xact-B sep xact-A))
    (goto-char (ledger-navigate-beginning-of-xact))))

(define-key ledger-mode-map [(meta up)] 'ledger-move-transaction-up)
(define-key ledger-mode-map [(meta down)] 'ledger-move-transaction-down)