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;;; srfi-31.scm --- special form for recursive evaluation
;; Copyright (C) 2004, 2006, 2012 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
;;; Original author: Rob Browning <rlb@defaultvalue.org>
(define-module (srfi srfi-31)
#:export (rec))
(cond-expand-provide (current-module) '(srfi-31))
(define-syntax rec
(syntax-rules ()
"Return the given object, defined in a lexical environment where
NAME is bound to itself."
((_ (name . formals) body ...) ; procedure
(letrec ((name (lambda formals body ...)))
name))
((_ name expr) ; arbitrary object
(letrec ((name expr))
name))))
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