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+;;; cl-preloaded.el --- Preloaded part of the CL library  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2015  Free Software Foundation, Inc
+
+;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
+
+;; 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 <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; The expectation is that structs defined with cl-defstruct do not
+;; need cl-lib at run-time, but we'd like to hide the details of the
+;; cl-struct metadata behind the cl-struct-define function, so we put
+;; it in this pre-loaded file.
+
+;;; Code:
+
+(defun cl-struct-define (name docstring parent type named slots children-sym
+                              tag print-auto)
+  (if (boundp children-sym)
+      (add-to-list children-sym tag)
+    (set children-sym (list tag)))
+  ;; If the cl-generic support, we need to be able to check
+  ;; if a vector is a cl-struct object, without knowing its particular type.
+  ;; So we use the (otherwise) unused function slots of the tag symbol
+  ;; to put a special witness value, to make the check easy and reliable.
+  (unless named (fset tag :quick-object-witness-check))
+  (put name 'cl-struct-slots slots)
+  (put name 'cl-struct-type (list type named))
+  (if parent (put name 'cl-struct-include parent))
+  (if print-auto (put name 'cl-struct-print print-auto))
+  (if docstring (put name 'structure-documentation docstring)))
+
+(provide 'cl-preloaded)
+;;; cl-preloaded.el ends here