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   1 ;;; cl-preloaded.el --- Preloaded part of the CL library  -*- lexical-binding: t; -*-
   2
   3 ;; Copyright (C) 2015  Free Software Foundation, Inc
   4
   5 ;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
   6
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  21
  22 ;;; Commentary:
  23
  24 ;; The expectation is that structs defined with cl-defstruct do not
  25 ;; need cl-lib at run-time, but we'd like to hide the details of the
  26 ;; cl-struct metadata behind the cl-struct-define function, so we put
  27 ;; it in this pre-loaded file.
  28
  29 ;;; Code:
  30
  31 (defun cl-struct-define (name docstring parent type named slots children-sym
  32                               tag print-auto)
  33   (if (boundp children-sym)
  34       (add-to-list children-sym tag)
  35     (set children-sym (list tag)))
  36   ;; If the cl-generic support, we need to be able to check
  37   ;; if a vector is a cl-struct object, without knowing its particular type.
  38   ;; So we use the (otherwise) unused function slots of the tag symbol
  39   ;; to put a special witness value, to make the check easy and reliable.
  40   (unless named (fset tag :quick-object-witness-check))
  41   (put name 'cl-struct-slots slots)
  42   (put name 'cl-struct-type (list type named))
  43   (if parent (put name 'cl-struct-include parent))
  44   (if print-auto (put name 'cl-struct-print print-auto))
  45   (if docstring (put name 'structure-documentation docstring)))
  46
  47 (provide 'cl-preloaded)
  48 ;;; cl-preloaded.el ends here