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diff --git a/gnu/gnunet/utils/cut-syntax.scm b/gnu/gnunet/utils/cut-syntax.scm
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+;; This file is part of Scheme-GNUnet
+;; Copyright © 2022 GNUnet e.V.
+;;
+;; Scheme-GNUnet is free software: you can redistribute it and/or modify it
+;; under the terms of the GNU Affero General Public License as published
+;; by the Free Software Foundation, either version 3 of the License,
+;; or (at your option) any later version.
+;;
+;; Scheme-GNUnet 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
+;; Affero General Public License for more details.
+;;
+;; You should have received a copy of the GNU Affero General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+;;
+;; SPDX-License-Identifier: AGPL-3.0-or-later
+
+;; TODO: eliminate (gnu gnunet netstruct syntactic), use a compiler pass instead
+;; for inlining, then ‘cut-syntax’ can be deprecated in favour of a ‘cut’.
+(define-library (gnu gnunet utils cut-syntax)
+  (export cut-syntax)
+  (import (only (rnrs base) ... begin define-syntax syntax-rules))
+  (begin
+    (define-syntax substitute
+      (syntax-rules (<>)
+        ((_ (substituted ...) (<> . foos) (bar . bars))
+         (substitute (substituted ... bar) foos bars))
+        ((_ (substituted ...) (foo . foos) bars)
+         (substitute (substituted ... foo) foos bars))
+        ((_ (substituted ...) () ())
+         (substituted ...))))
+
+    (define-syntax cut-syntax
+      (syntax-rules ()
+        ((_ . foos)
+         (syntax-rules ()
+           ((_ . bars) (substitute () foos bars))))))))