;;;; REQUIRE, PROVIDE, and friends
;;;; Officially these are deprecated, but in practice they're probably
;;;; even less likely to actually go away than there is to ever be
;;;; another revision of the standard.
;;;; This software is part of the SBCL system. See the README file for
;;;; more information.
;;;; This software is derived from the CMU CL system, which was
;;;; written at Carnegie Mellon University and released into the
;;;; public domain. The software is in the public domain and is
;;;; provided with absolutely no warranty. See the COPYING and CREDITS
;;;; files for more information.
;;;; exported specials
(defvar *modules* ()
"This is a list of module names that have been loaded into Lisp so far.
It is used by PROVIDE and REQUIRE.")
(defvar *module-provider-functions* (list 'module-provide-contrib)
"See function documentation for REQUIRE.")
;;;; PROVIDE and REQUIRE
(defun provide (module-name)
"Adds a new module name to *MODULES* indicating that it has been loaded.
Module-name is a string designator"
(pushnew (string module-name) *modules* :test #'string=)
(defvar *requiring* nil)
(defun require-error (control &rest arguments)
'(:sbcl :variable *module-provider-functions*)
'(:sbcl :function require))))
(defun require (module-name &optional pathnames)
"Loads a module, unless it already has been loaded. PATHNAMES, if supplied,
is a designator for a list of pathnames to be loaded if the module
needs to be. If PATHNAMES is not supplied, functions from the list
*MODULE-PROVIDER-FUNCTIONS* are called in order with MODULE-NAME
as an argument, until one of them returns non-NIL. User code is
responsible for calling PROVIDE to indicate a successful load of the
(let ((name (string module-name)))
(when (member name *requiring* :test #'string=)
(require-error "~@<Could not ~S ~A: circularity detected. Please check ~
your configuration.~:@>" 'require module-name))
(let ((saved-modules (copy-list *modules*))
(*requiring* (cons name *requiring*)))
(unless (member name *modules* :test #'string=)
(unless (listp pathnames) (setf pathnames (list pathnames)))
;; ambiguity in standard: should we try all pathnames in the
;; list, or should we stop as soon as one of them calls PROVIDE?
(dolist (ele pathnames t)
(unless (some (lambda (p) (funcall p module-name))
(require-error "Don't know how to ~S ~A."
(set-difference *modules* saved-modules))))
(defun module-provide-contrib (name)
"Stringify and downcase NAME, then attempt to load the file
(let* ((filesys-name (string-downcase (string name)))
(make-pathname :directory (list :relative "contrib")
(truename (or (sbcl-homedir-pathname)
(return-from module-provide-contrib nil)))))
(make-pathname :type *fasl-file-type*)
(lisp-path (merge-pathnames (make-pathname :type "lisp")
;; KLUDGE: there's a race condition here; the file we probe could
;; be removed by the time we get round to trying to load it.
;; Maybe factor out the logic in the LOAD guesser as to which file
;; was meant, so that we can use it here on open streams instead?
(let ((file (or (probe-file fasl-path)
(((or style-warning sb!int:package-at-variance) #'muffle-warning))