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Handle varalias chains, custom variables in #'user-variable-p. src/ChangeLog addition: 2008-08-23 Aidan Kehoe <kehoea@parhasard.net> * eval.c (Fuser_variable_p): Moved to symbols.c * symbols.c (Fcustom_variable_p): Moved here from custom.el. (user_variable_alias_check_fun): Mapper function used in `user-variable-p'. (Fuser_variable_p): Moved here from eval.c, to allow it to examine the variable alias chain. Expanded to check each entry in the variable alias chain for signs of being a user variable; documentation updated, noting the differences between GNU's behaviour and ours (ours is a little more sensible) (map_varalias_chain): New. Given a C function, call it at least once for each symbol in a symbol's varalias chain, signalling an error if there's a cycle, and returning immediately if the function returns something other than Qzero. (Fdefvaralias): Correct the use of the word "alias" in the docstring and in the argument name. Motivate this in a comment. Add support for a DOCSTRING argument, something GNU has too, and document this * gc.c (vars_of_gc): Start the docstring of `garbage-collection-messages' with an asterisk, to indicate that it's a user variable. lisp/ChangeLog addition: 2008-08-23 Aidan Kehoe <kehoea@parhasard.net> * custom.el: Move #'custom-variable-p to C, since it's now called from #'user-variable-p.
author Aidan Kehoe <kehoea@parhasard.net>
date Sat, 23 Aug 2008 16:38:51 +0200
parents 576fb035e263
children 308d34e9f07d
line wrap: on
line source

;;; float-sup.el --- detect absence of floating-point support in XEmacs runtime

;; Copyright (C) 1985-7, 1997 Free Software Foundation, Inc.

;; Maintainer: FSF
;; Keywords: internal, dumped

;; This file is part of XEmacs.

;; XEmacs 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 2, or (at your option)
;; any later version.

;; XEmacs 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 XEmacs; see the file COPYING.  If not, write to the Free
;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
;; 02111-1307, USA.

;;; Synched up with: FSF 19.34.

;;; Code:

;; This file is dumped with XEmacs.

;; Provide a meaningful error message if we are running on
;; bare (non-float) emacs.
;; Can't test for 'floatp since that may be defined by float-imitation
;; packages like float.el in this very directory.

;; XEmacs change
(or (featurep 'lisp-float-type)
    (error "Floating point was disabled at compile time"))

;; define pi and e via math-lib calls. (much less prone to killer typos.)
(defconst pi (* 4 (atan 1)) "The value of Pi (3.1415926...)")
(defconst e (exp 1) "The value of e (2.7182818...)")

;; Careful when editing this file ... typos here will be hard to spot.
;; (defconst pi       3.14159265358979323846264338327
;;  "The value of Pi (3.14159265358979323846264338327...)")

(defconst degrees-to-radians (/ pi 180.0)
  "Degrees to radian conversion constant")
(defconst radians-to-degrees (/ 180.0 pi)
  "Radian to degree conversion constant")

;; these expand to a single multiply by a float when byte compiled

(defmacro degrees-to-radians (x)
  "Convert ARG from degrees to radians."
  (list '* (/ pi 180.0) x))
(defmacro radians-to-degrees (x)
  "Convert ARG from radians to degrees."
  (list '* (/ 180.0 pi) x))

;; Provided in C code in XEmacs
;; (provide 'lisp-float-type)

;;; float-sup.el ends here