diff lisp/prim/float-sup.el @ 0:376386a54a3c r19-14

Import from CVS: tag r19-14
author cvs
date Mon, 13 Aug 2007 08:45:50 +0200
parents
children ac2d302a0011
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lisp/prim/float-sup.el	Mon Aug 13 08:45:50 2007 +0200
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+;;; float-sup.el --- detect absence of floating-point support in XEmacs runtime
+
+;; Copyright (C) 1985, 1986, 1987 Free Software Foundation, Inc.
+
+;; Maintainer: FSF
+;; Keywords: internal
+
+;; 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+;;; Synched up with: FSF 19.30.
+
+;; 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.
+
+(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 (purecopy (* 4 (atan 1))) "The value of Pi (3.1415926...)")
+(defconst e (purecopy (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 (purecopy (/ pi 180.0))
+  "Degrees to radian conversion constant")
+(defconst radians-to-degrees (purecopy (/ 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))
+
+;;; float-sup.el ends here