(define-datatype continuation continuation?
  (rep-cont)
  (eval-cont
   (exps (list-of expression?))
   (cont continuation?)
   (env scheme-value?))
  (eval-bodies-cont
   (exps (list-of expression?))
   (cont continuation?)
   (env scheme-value?))  
  (call/cc-cont
   (cont continuation?))
  (cons-cont
   (value scheme-value?)
   (cont continuation?))
  (proc-cont
   (cont continuation?))
  (if-cont
   (true-exp expression?)
   (false-exp expression?)
   (next-cont continuation?)
   (env pair?)))


(define apply-cont
  (lambda (cont val)
    (cases continuation cont
	   [rep-cont ()
		      (pretty-print val)
		      (rep)]
	   [call/cc-cont (cont)
			 (cases proc val
				[closure (ids bodies env)
					 (eval-expressions bodies
							   cont
							   (extend-env ids
								       (list (acontinuation cont))
								       env))]
				[else (eopl:error 'apply-cont "Continuation is not a procedure ~s" val)])]					 
	   [eval-cont (exps cont env)
		      (eval-expressions exps (cons-cont val cont) env)]
	   [eval-bodies-cont (exps cont env)
			     (eval-bodies exps cont env)]
           [proc-cont (cont)
		      (if (proc? (caar val))
			  (apply-procedure (caar val) (cdr val) cont)
			  (apply-procedure (car val) (cdr val) cont))]
	   [cons-cont (value cont)
		      (apply-cont cont (cons value val))]
	   [if-cont (true-exp false-exp next-cont env)
		    (if val
			(eval-expression true-exp next-cont env)
			(eval-expression false-exp next-cont env))])))