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+;; Copyright 2025
+;; Kaz Kylheku <kaz@kylheku.com>
+;; Vancouver, Canada
+;; 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.
+;;
+;; 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 HOLDER 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.
+
+(defun normalize-enum-pairs (f enum-pairs)
+  (let ((n 0))
+    (keep-matches (@(or (@sym @init)
+                        @(with @sym init n))
+                    enum-pairs)
+      (unless (bindable sym)
+        (compile-error f "~s isn't a bindable symbol" sym))
+      (unless (or (integerp init) (chrp init))
+        (compile-error f "~s must be an integer or character" init))
+      (set n (succ init))
+      ^(,sym ,init))))
+                   
+(defmacro defenum (:form f . enum-pairs)
+  (let ((nep (normalize-enum-pairs f enum-pairs)))
+    ^(progn ,*(mapcar (op cons 'defsymacro) nep))))
+
+(defmacro enumlet (:form f enum-pairs . body)
+  (let ((nep (normalize-enum-pairs f enum-pairs)))
+    ^(symacrolet ,nep ,*body)))