(import (except (srfi 180) json-null)
	(scheme case-lambda)
	(srfi 1)
	(srfi 2))
(begin
  (define json-object list)
  (define json-list vector)
  (define json-null 'null)

  (define (json-object? j)
    (or (list? j)
	(json-record? j)))

  (define json-list? vector?)
  ;; json-null? already defined in srfi 180

  (define (json-object-contains-key? obj key)
    (or (and (list? obj)
	     (assoc key obj)
	     #t)
	(and (json-record? obj)
	     (json-object-contains-key? (json-record->fields obj) key))))

  (define (string->json str)
    (call-with-port (open-input-string str)
      (lambda (port)
	(json-read port))))

  (define (json->string json)
    (call-with-port (open-output-string)
      (lambda (port)
	(json-write (json->typeless-json json) port)
	(get-output-string port))))

  (define (json-object-ref json key)
    (cond
     ((list? json)
      (let ((pair (assoc key json)))
	(if pair
	    (cdr pair)
	    ((json-key-not-found)))))
     ((json-record? json)
      (json-object-ref (json-record->fields json) key))
     (else ((key-not-found)))))

  (define (json-object-set! json key value)
    (cond
     ((and (list? json)
	   (json-object-contains-key? json key))
      (json-object-map (lambda (k v)
			 (if (eq? k key)
			     (values k value)
			     (values k v)))
		       json))
     ((null? json)
      (json-object (cons key value)))
     ((list? json)
      (append! json (list (cons key value))))
     ((json-record? json)
      (or (and-let* ((pair (assoc key (json-record->mutators json)))
		     (mutator (cdr pair)))
	    (mutator json value))
	  (error "json-object-set!: no mutator for field" (json-record->name json) key)))))

  (define json-list-ref vector-ref)
  (define json-list-length vector-length)

  (define (json-object-map proc json)
    (map (lambda (pair)
	   (call-with-values (lambda () (proc (car pair) (cdr pair)))
	     (case-lambda
	       ((key value) (cons key value))
	       (_ (error "json-object-map: proc did not return two values")))))
	 json))

  (define json-list-map vector-map)

  (define (json-object->alist obj)
    (cond
     ((list? obj) obj)
     ((json-record? obj) (json-record->fields obj))
     (else (error "json-object->alist: not an object" obj))))

  (define json-list->list vector->list))