src/cold/rename-package-carefully.lisp

   1 ;;;; This software is part of the SBCL system. See the README file for
   2 ;;;; more information.
   3 ;;;;
   4 ;;;; This software is derived from the CMU CL system, which was
   5 ;;;; written at Carnegie Mellon University and released into the
   6 ;;;; public domain. The software is in the public domain and is
   7 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
   8 ;;;; files for more information.
   9
  10 (in-package "SB-COLD")
  11
  12 ;;; RENAME-PACKAGE in two steps in order to avoid the possibility of undefined
  13 ;;; behavior when one of the new names is the same as one of the old names.
  14 ;;; (ANSI on RENAME-PACKAGE: "The consequences are undefined if new-name or any
  15 ;;; new-nickname conflicts with any existing package names.")
  16 (defun rename-package-carefully (package-designator
  17                                  new-name
  18                                  &optional new-nicknames)
  19   (let ((package (find-package package-designator))
  20         (unused-name "UNUSED-PACKAGE-NAME"))
  21     (assert (not (find-package unused-name)))
  22     (assert (not (string= unused-name new-name)))
  23     (assert (not (find unused-name new-nicknames :test #'string=)))
  24     (assert (not (find new-name new-nicknames :test #'string=)))
  25     (rename-package package unused-name)
  26     (rename-package package new-name new-nicknames)))
  27 (compile 'rename-package-carefully)