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diff --git a/share/txr/stdlib/except.tl b/share/txr/stdlib/except.tl
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+;; Copyright 2015
+;; Kaz Kylheku <kaz@kylheku.com>
+;; Vancouver, Canada
+;; All rights reserved.
+;;
+;; Redistribution of this software in source and binary forms, with or without
+;; modification, is permitted provided that the following two conditions are met.
+;;
+;; Use of this software in any manner constitutes agreement with the disclaimer
+;; which follows the two conditions.
+;;
+;; 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.
+;;
+;; THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+;; WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+;; MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL THE
+;; COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DAMAGES, HOWEVER CAUSED,
+;; AND UNDER ANY THEORY OF LIABILITY, ARISING IN ANY WAY OUT OF THE USE OF THIS
+;; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+(defun sys:handle-bad-syntax (item)
+  (throwf 'eval-error "~s: bad clause syntax: ~s" 'handle item))
+
+(defmacro handle (:whole form try-form . handle-clauses)
+  (let* ((exc-sym (gensym))
+         (exc-args (gensym))
+         (syms-fragments (collect-each ((hc handle-clauses))
+                          (tree-case hc
+                            ((name arglist . body)
+                             (unless (symbolp name)
+                               (sys:handle-bad-syntax hc))
+                             (list name ^(apply (lambda ,arglist ,*body)
+                                                ,exc-sym ,exc-args)))
+                            (else (sys:handle-bad-syntax hc))))))
+    ^(handler-bind (lambda (,exc-sym . ,exc-args)
+                     (cond
+                       ,*(mapcar (aret ^((exception-subtype-p ,exc-sym ',@1) ,@2))
+                                 syms-fragments)))
+                   ,[mapcar car syms-fragments]
+                   ,try-form)))