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- ;; Filename : srfi-55.scm
- ;; About : SRFI-55 require-extension
- ;;
- ;; Copyright (c) 2007-2008 SigScheme Project <uim-en AT googlegroups.com>
- ;;
- ;; All rights reserved.
- ;;
- ;; Redistribution and use in source and binary forms, with or without
- ;; modification, are permitted provided that the following conditions
- ;; are met:
- ;;
- ;; 1. Redistributions of source code must retain the above copyright
- ;; notice, this list of conditions and the following disclaimer.
- ;; 2. Redistributions in binary form must reproduce the above copyright
- ;; notice, this list of conditions and the following disclaimer in the
- ;; documentation and/or other materials provided with the distribution.
- ;; 3. Neither the name of authors nor the names of its contributors
- ;; may be used to endorse or promote products derived from this software
- ;; without specific prior written permission.
- ;;
- ;; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
- ;; IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- ;; THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- ;; PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
- ;; CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- ;; EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- ;; PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- ;; PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- ;; LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- ;; NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- ;; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-
- (define %require-extension-handler-srfi
- (lambda numbers
- (for-each (lambda (n)
- (let ((srfi-n (string-append "srfi-" (number->string n))))
- (or (%%require-module srfi-n)
- (%require-sysfile srfi-n))))
- numbers)))
-
- ;; Be quasiquote free to allow --disable-quasiquote
- (define %require-extension-alist
- (list
- (cons 'srfi %require-extension-handler-srfi)))
-
- (define %require-sysfile
- (lambda (ext-id)
- (or (provided? ext-id)
- (let* ((file (string-append ext-id ".scm"))
- (path (string-append (%%system-load-path) "/" file)))
- (load path)
- (provide ext-id)))))
-
- (define %require-extension
- (lambda clauses
- (for-each (lambda (clause)
- (let* ((id (car clause))
- (args (cdr clause))
- (id-str (symbol->string id))
- (default-handler (lambda ()
- (or (%%require-module id-str)
- (%require-sysfile id-str))))
- (handler (cond
- ((assq id %require-extension-alist) => cdr)
- (else
- default-handler))))
- (apply handler args)))
- clauses)))
-