Method: (MAP-TRANSACTIONS STANDARD-CACHE T)

Source

(defmethod map-transactions ((cache standard-cache) function)
  ;; FUNCTION may be a function that closes the transaction (removing
  ;; it from the hash table), so we create a fresh list with transactions
  ;; before doing the actual iteration.
  (let ((transactions '()))
    (loop for transaction being the hash-value of (transactions cache)
          do (push transaction transactions))
    ;; Now we can iterate safely.
    (mapc function transactions)))