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+;;; indent-aux.el --- Autoloaded indentation commands for Emacs  -*- lexical-binding:t -*-
+
+;; Copyright (C) 2023-2024 Free Software Foundation, Inc.
+
+;; Maintainer: emacs-devel@gnu.org
+;; Package: emacs
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs 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 General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Autoloaded commands for making and changing indentation in text and
+;; killed text
+
+;;; Code:
+
+
+
+;; Indent Filter mode.  When enabled, this minor mode filters all
+;; killed text to remove leading indentation.
+
+(defun kill-ring-deindent-buffer-substring-function (beg end delete)
+  "Save the text within BEG and END to kill-ring, decreasing indentation.
+Delete the saved text if DELETE is non-nil.
+
+In the saved copy of the text, remove some of the indentation, such
+that the buffer position at BEG will be at column zero when the text
+is yanked."
+  (let ((a beg)
+        (b end))
+    (setq beg (min a b)
+          end (max a b)))
+  (let ((indentation (save-excursion (goto-char beg)
+                                     (current-column)))
+        (text (if delete
+                  (delete-and-extract-region beg end)
+                (buffer-substring beg end))))
+    (with-temp-buffer
+      (insert text)
+      (indent-rigidly (point-min) (point-max)
+                      (- indentation))
+      (buffer-string))))
+
+;;;###autoload
+(define-minor-mode kill-ring-deindent-mode
+  "Toggle removal of indentation from text saved to the kill ring.
+
+When this minor mode is enabled, text saved into the kill ring is
+indented towards the left by the column number at the start of
+that text."
+  :global 't
+  :group 'killing
+  (if kill-ring-deindent-mode
+      (add-function :override filter-buffer-substring-function
+                    #'kill-ring-deindent-buffer-substring-function
+                    '(:depth 100))
+    (remove-function filter-buffer-substring-function
+                     #'kill-ring-deindent-buffer-substring-function)))
+
+
+
+(provide 'indent-aux)
+;;; indent-aux.el ends here.