anchor.diff:  (define call/ec call-with-escape-continuation)
   (define-macro let/ec let-escape-continuation)
   
  -(defun continue (k &args)
  -  "Continue execution of K with ARGS as the arguments.
  -
  -   ### Example
  -   ```cl
  -   > (continue (coroutine/create
  -   .             (lambda () (+ 1 (coroutine/yield))))
  -   .           2)
  -   out = 3
  -   ```"
  +(defun continue (k &args) :hidden
     (let* [(last-res nil)]
       (while (/= (c/status k) :dead)
         (let* [((ok err) (c/resume k (unpack args 1 (n args))))]
  
positive.code: (import lua/coroutine c)
  
  (defun call-with-prompt (prompt-tag body handler)
    "Call the thunk BODY with a prompt PROMPT-TAG in scope. If BODY
  
negative.code:                 (>= (n err) 2)
                  (eq? (car err) :abort))
             (if (eq? (cadr err) prompt-tag)
               (handler (reify-continuation k) (cddr err))
               (abort-to-prompt (cadr err) (unpack (cddr err) 1
                                                   (n (cddr err)))))]
            [(! ok)
  