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+;;;; and-let-star.scm --- and-let* syntactic form (draft SRFI-2) for Guile
+;;;; written by Michael Livshin <mike@olan.com>
+;;;;
+;;;; Copyright (C) 1999, 2001, 2004, 2006 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 2.1 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
+
+(define-module (ice-9 and-let-star)
+ :export-syntax (and-let*))
+
+(defmacro and-let* (vars . body)
+
+ (define (expand vars body)
+ (cond
+ ((null? vars)
+ (if (null? body)
+ #t
+ `(begin ,@body)))
+ ((pair? vars)
+ (let ((exp (car vars)))
+ (cond
+ ((pair? exp)
+ (cond
+ ((null? (cdr exp))
+ `(and ,(car exp) ,(expand (cdr vars) body)))
+ (else
+ (let ((var (car exp)))
+ `(let (,exp)
+ (and ,var ,(expand (cdr vars) body)))))))
+ (else
+ `(and ,exp ,(expand (cdr vars) body))))))
+ (else
+ (error "not a proper list" vars))))
+
+ (expand vars body))
+
+(cond-expand-provide (current-module) '(srfi-2))