mirror of
https://git.savannah.gnu.org/git/guile.git
synced 2025-04-29 19:30:36 +02:00
37 lines
1.3 KiB
Scheme
37 lines
1.3 KiB
Scheme
;;; srfi-111.scm -- SRFI 111 Boxes
|
|
|
|
;; Copyright (C) 2014 Free Software Foundation, Inc.
|
|
;;
|
|
;; This library is free software; you can redistribute it and/or
|
|
;; modify it under the terms of the GNU Lesser General Public
|
|
;; License as published by the Free Software Foundation; either
|
|
;; version 3 of the License, or (at your option) any later version.
|
|
;;
|
|
;; This library is distributed in the hope that it will be useful,
|
|
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
;; Lesser General Public License for more details.
|
|
;;
|
|
;; You should have received a copy of the GNU Lesser General Public
|
|
;; License along with this library; if not, write to the Free Software
|
|
;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
(define-module (srfi srfi-111)
|
|
#:use-module (srfi srfi-9)
|
|
#:use-module (srfi srfi-9 gnu)
|
|
#:export (box box? unbox set-box!))
|
|
|
|
(cond-expand-provide (current-module) '(srfi-111))
|
|
|
|
(define-record-type <box>
|
|
(box value)
|
|
box?
|
|
(value unbox set-box!))
|
|
|
|
(set-record-type-printer! <box>
|
|
(lambda (box port)
|
|
(display "#<box " port)
|
|
(display (number->string (object-address box) 16) port)
|
|
(display " value: " port)
|
|
(write (unbox box) port)
|
|
(display ">" port)))
|