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+;;"srfi-2.scm": Guarded LET* special form
+;Copyright (C) 2003 Aubrey Jaffer
+;
+;Permission to copy this software, to modify it, to redistribute it,
+;to distribute modified versions, and to use it for any purpose is
+;granted, subject to the following restrictions and understandings.
+;
+;1.  Any copy made of this software must include this copyright notice
+;in full.
+;
+;2.  I have made no warranty or representation that the operation of
+;this software will be error-free, and I am under no obligation to
+;provide any services, by way of maintenance, update, or otherwise.
+;
+;3.  In conjunction with products arising from the use of this
+;material, there shall be no use of my name in any advertising,
+;promotional, or sales literature without prior written consent in
+;each case.
+
+;;@code{(require 'srfi-2)}
+;;@ftindex srfi-2
+
+;;@body
+;;@url{http://srfi.schemers.org/srfi-2/srfi-2.html}
+(defmacro and-let* (claws . body)
+  (define (andin claw ans)
+    (if (and (pair? ans) (eq? 'and (car ans)))
+	`(and ,claw ,@(cdr ans))
+	`(and ,claw ,ans)))
+  (do ((claws (reverse claws) (cdr claws))
+       (ans (cond ((null? body) '(and))
+		  ((null? (cdr body)) (car body))
+		  (else (cons 'begin body)))
+	    (let ((claw (car claws)))
+	      (cond ((symbol? claw)
+		     (andin claw ans))
+		    ((and (pair? claw) (null? (cdr claw)))
+		     (andin (car claw) ans))
+		    (else
+		     `(let (,claw) ,(andin (car claw) ans)))))))
+      ((null? claws) ans)))