1 ;;; very-early-lisp.el --- Lisp support always needed by temacs
3 ;; Copyright (C) 1998 by Free Software Foundation, Inc.
5 ;; Author: SL Baur <steve@altair.xemacs.org>
6 ;; Michael Sperber [Mr. Preprocessor] <sperber@Informatik.Uni-Tuebingen.De>
7 ;; Keywords: internal, dumped
9 ;; This file is part of XEmacs.
11 ;; XEmacs is free software; you can redistribute it and/or modify it
12 ;; under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation; either version 2, or (at your option)
16 ;; XEmacs is distributed in the hope that it will be useful, but
17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 ;; General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with XEmacs; see the file COPYING. If not, write to the Free
23 ;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
26 ;;; Synched up with: Not in FSF
30 ;; This file must be loaded by temacs if temacs is to process bytecode
31 ;; or dumped-lisp.el files.
35 ;;; Intended replacement for read-time Lisp reader macros #-, #+
37 (defmacro assemble-list (&rest components)
38 "Assemble a list from COMPONENTS.
39 This is a poor man's backquote:
40 COMPONENTS is a list, each element of which is macro-expanded.
41 Each macro-expanded element either has the form (SPLICE stuff),
42 in which case stuff must be a list which is spliced into the result.
43 Otherwise, the component becomes an element of the list."
46 (mapcar #'(lambda (component)
47 (let ((component (macroexpand-internal component)))
48 (if (and (consp component)
49 (eq 'splice (car component)))
51 (list 'list component))))
54 (defmacro when-feature (feature stuff)
55 "Insert STUFF as a list element if FEATURE is a loaded feature.
56 This is intended for use as a component of ASSEMBLE-LIST."
58 (list 'if (list 'featurep (list 'quote feature))
62 (defmacro unless-feature (feature stuff)
63 "Insert STUFF as a list element if FEATURE is NOT a loaded feature.
64 This is intended for use as a component of ASSEMBLE-LIST."
66 (list 'if (list 'featurep (list 'quote feature))
70 (provide 'very-early-lisp)
72 ;;; very-early-lisp.el ends here