;;; Gash -- Guile As SHell
;;; Copyright © 2018 Timothy Sample <samplet@ngyro.com>
;;;
;;; This file is part of Gash.
;;;
;;; Gash is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; Gash 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 General Public License for more
;;; details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.

(define-module (gash built-ins exit)
  #:use-module (gash environment))

;;; Commentary:
;;;
;;; The 'exit' utility.
;;;
;;; Code:

(define (main . args)
  (let* ((arg (or (and (pair? args)
                       (car (last-pair args)))
                  (number->string (get-status))
                  "0"))
         (number (string->number arg))
         (status (or (and (exact-integer? number)
                          (>= number 0)
                          (<= number 256)
                          number)
                     ;; If the above is not true, the exit status is
                     ;; undefined.
                     EXIT_FAILURE)))
    (sh:exit status)))
