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+;;; compat.el --- Stub of the Compatibility Library -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2021-2024 Free Software Foundation, Inc.
+
+;; Author:								\
+;;   Philip Kaludercic <philipk@posteo.net>,				\
+;;   Daniel Mendler <mail@daniel-mendler.de>
+;; Maintainer:								\
+;;   Daniel Mendler <mail@daniel-mendler.de>,				\
+;;   Compat Development <~pkal/compat-devel@lists.sr.ht>,
+;;   emacs-devel@gnu.org
+;; URL: https://github.com/emacs-compat/compat
+;; Keywords: lisp, maint
+
+;; This program 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.
+
+;; This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; The Compat package on ELPA provides forward-compatibility
+;; definitions for other packages.  While mostly transparent, a
+;; minimal API is necessary whenever core definitions change calling
+;; conventions (e.g. `plist-get' can be invoked with a predicate from
+;; Emacs 29.1 onward).  For core packages on ELPA to be able to take
+;; advantage of this functionality, the macros `compat-function' and
+;; `compat-call' have to be available in the core, usable even if
+;; users do not have the Compat package installed, which this file
+;; ensures.
+
+;; A basic introduction to Compat is given in the Info node `(elisp)
+;; Forwards Compatibility'.  Further details on Compat are documented
+;; in the Info node `(compat) Top' (installed along with the Compat
+;; package) or read the same manual online:
+;; https://elpa.gnu.org/packages/doc/compat.html.
+
+;;; Code:
+
+(defmacro compat-function (fun)
+  "Return compatibility function symbol for FUN.
+This is a pseudo-compatibility stub for core packages on ELPA,
+that depend on the Compat package, whenever the user doesn't have
+the package installed on their current system."
+  `#',fun)
+
+(defmacro compat-call (fun &rest args)
+  "Call compatibility function or macro FUN with ARGS.
+This is a pseudo-compatibility stub for core packages on ELPA,
+that depend on the Compat package, whenever the user doesn't have
+the package installed on their current system."
+  (cons fun args))
+
+;;;; Clever trick to avoid installing Compat if not necessary
+
+;; The versioning scheme of the Compat package follows that of Emacs,
+;; to indicate the version of Emacs, that functionality is being
+;; provided for.  For example, the Compat version number 29.2.3.9
+;; would attempt to provide compatibility definitions up to Emacs
+;; 29.2, while also designating that this is the third major release
+;; and ninth minor release of Compat, for the specific Emacs release.
+
+;; The package version of this file is specified programmatically,
+;; instead of giving a fixed version in the header of this file.  This
+;; is done to ensure that the version of compat.el provided by Emacs
+;; always corresponds to the current version of Emacs.  In addition to
+;; the major-minor version, a large "major release" makes sure that
+;; the built-in version of Compat is always preferred over an external
+;; installation.  This means that if a package specifies a dependency
+;; on Compat which matches the current or an older version of Emacs
+;; that is being used, no additional dependencies have to be
+;; downloaded.
+;;
+;; Further details and background on this file can be found in the
+;; bug#66554 discussion.
+
+;;;###autoload (push (list 'compat
+;;;###autoload             emacs-major-version
+;;;###autoload             emacs-minor-version
+;;;###autoload             9999)
+;;;###autoload       package--builtin-versions)
+
+(provide 'compat)
+;;; compat.el ends here