;;; "recobj.scm" Records implemented as objects.
;;; Author: Wade Humeniuk <humeniuw@cadvision.com>
;;;
;;; This code is in the public domain.
(require 'object)
(require 'common-list-functions)
(define field:position position)
;@
(define record-type-name (make-generic-method))
(define record-accessor (make-generic-method))
(define record-modifier (make-generic-method))
(define record? (make-generic-predicate))
(define record-constructor (make-generic-method))
;@
(define (make-record-type type-name field-names)
(define self (make-object))
(make-method! self record-type-name
(lambda (self)
type-name))
(make-method! self record-accessor
(lambda (self field-name)
(let ((index (field:position field-name field-names)))
(if (not index)
(slib:error "record-accessor: invalid field-name argument."
field-name))
(lambda (obj)
(record-accessor obj index)))))
(make-method! self record-modifier
(lambda (self field-name)
(let ((index (field:position field-name field-names)))
(if (not index)
(slib:error "record-accessor: invalid field-name argument."
field-name))
(lambda (obj newval)
(record-modifier obj index newval)))))
(make-method! self record? (lambda (self) #t))
(make-method! self record-constructor
(lambda (class . field-values)
(let ((values (apply vector field-values)))
(define self (make-object))
(make-method! self record-accessor
(lambda (self index)
(vector-ref values index)))
(make-method! self record-modifier
(lambda (self index newval)
(vector-set! values index newval)))
(make-method! self record-type-name
(lambda (self) (record-type-name class)))
self)))
self)
(provide 'record-object)
(provide 'record)