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add functions `stable-union' and `stable-intersection' to do stable set operations -------------------- ChangeLog entries follow: -------------------- lisp/ChangeLog addition: 2010-02-22 Ben Wing <ben@xemacs.org> * cl-seq.el: * cl-seq.el (stable-union): New. * cl-seq.el (stable-intersection): New. New functions to do stable set operations, i.e. preserve the order of the elements in the argument lists, and prefer LIST1 over LIST2 when ordering the combined result. The result looks as much like LIST1 as possible, followed (in the case of `stable-union') by any necessary elements from LIST2, in order. This is contrary to `union' and `intersection', which are not required to be order- preserving and are not -- they prefer LIST2 and output results in backwards order.
author Ben Wing <ben@xemacs.org>
date Mon, 22 Feb 2010 21:23:02 -0600
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