lisp/emacs-lisp/cl-compat.el

   1 ;;; cl-compat.el --- Common Lisp extensions for GNU Emacs Lisp (compatibility)
   2
   3 ;; Copyright (C) 1993, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4
   5 ;; Author: Dave Gillespie <daveg@synaptics.com>
   6 ;; Version: 2.02
   7 ;; Keywords: extensions
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; These are extensions to Emacs Lisp that provide a degree of
  29 ;; Common Lisp compatibility, beyond what is already built-in
  30 ;; in Emacs Lisp.
  31 ;;
  32 ;; This package was written by Dave Gillespie; it is a complete
  33 ;; rewrite of Cesar Quiroz's original cl.el package of December 1986.
  34 ;;
  35 ;; This package works with Emacs 18, Emacs 19, and Lucid Emacs 19.
  36 ;;
  37 ;; Bug reports, comments, and suggestions are welcome!
  38
  39 ;; This file contains emulations of internal routines of the older
  40 ;; CL package which users may have called directly from their code.
  41 ;; Use (require 'cl-compat) to get these routines.
  42
  43 ;; See cl.el for Change Log.
  44
  45
  46 ;;; Code:
  47
  48 ;; Require at load-time, but not when compiling cl-compat.
  49 (or (featurep 'cl) (require 'cl))
  50
  51
  52 ;;; Keyword routines not supported by new package.
  53
  54 (defmacro defkeyword (x &optional doc)
  55   (list* 'defconst x (list 'quote x) (and doc (list doc))))
  56
  57 (defun keyword-of (sym)
  58   (or (keywordp sym) (keywordp (intern (format ":%s" sym)))))
  59
  60
  61 ;;; Multiple values.  Note that the new package uses a different
  62 ;;; convention for multiple values.  The following definitions
  63 ;;; emulate the old convention; all function names have been changed
  64 ;;; by capitalizing the first letter: Values, Multiple-value-*,
  65 ;;; to avoid conflict with the new-style definitions in cl-macs.
  66
  67 (put 'Multiple-value-bind  'lisp-indent-function 2)
  68 (put 'Multiple-value-setq  'lisp-indent-function 2)
  69 (put 'Multiple-value-call  'lisp-indent-function 1)
  70 (put 'Multiple-value-prog1 'lisp-indent-function 1)
  71
  72 (defvar *mvalues-values* nil)
  73
  74 (defun Values (&rest val-forms)
  75   (setq *mvalues-values* val-forms)
  76   (car val-forms))
  77
  78 (defun Values-list (val-forms)
  79   (apply 'values val-forms))
  80
  81 (defmacro Multiple-value-list (form)
  82   (list 'let* (list '(*mvalues-values* nil) (list '*mvalues-temp* form))
  83         '(or (and (eq *mvalues-temp* (car *mvalues-values*)) *mvalues-values*)
  84              (list *mvalues-temp*))))
  85
  86 (defmacro Multiple-value-call (function &rest args)
  87   (list 'apply function
  88         (cons 'append
  89               (mapcar (function (lambda (x) (list 'Multiple-value-list x)))
  90                       args))))
  91
  92 (defmacro Multiple-value-bind (vars form &rest body)
  93   (list* 'multiple-value-bind vars (list 'Multiple-value-list form) body))
  94
  95 (defmacro Multiple-value-setq (vars form)
  96   (list 'multiple-value-setq vars (list 'Multiple-value-list form)))
  97
  98 (defmacro Multiple-value-prog1 (form &rest body)
  99   (list 'prog1 form (list* 'let '((*mvalues-values* nil)) body)))
 100
 101
 102 ;;; Routines for parsing keyword arguments.
 103
 104 (defun build-klist (arglist keys &optional allow-others)
 105   (let ((res (Multiple-value-call 'mapcar* 'cons (unzip-lists arglist))))
 106     (or allow-others
 107         (let ((bad (set-difference (mapcar 'car res) keys)))
 108           (if bad (error "Bad keywords: %s not in %s" bad keys))))
 109     res))
 110
 111 (defun extract-from-klist (klist key &optional def)
 112   (let ((res (assq key klist))) (if res (cdr res) def)))
 113
 114 (defun keyword-argument-supplied-p (klist key)
 115   (assq key klist))
 116
 117 (defun elt-satisfies-test-p (item elt klist)
 118   (let ((test-not (cdr (assq ':test-not klist)))
 119         (test (cdr (assq ':test klist)))
 120         (key (cdr (assq ':key klist))))
 121     (if key (setq elt (funcall key elt)))
 122     (if test-not (not (funcall test-not item elt))
 123       (funcall (or test 'eql) item elt))))
 124
 125
 126 ;;; Rounding functions with old-style multiple value returns.
 127
 128 (defun cl-floor (a &optional b) (Values-list (floor* a b)))
 129 (defun cl-ceiling (a &optional b) (Values-list (ceiling* a b)))
 130 (defun cl-round (a &optional b) (Values-list (round* a b)))
 131 (defun cl-truncate (a &optional b) (Values-list (truncate* a b)))
 132
 133 (defun safe-idiv (a b)
 134   (let* ((q (/ (abs a) (abs b)))
 135          (s (* (signum a) (signum b))))
 136     (Values q (- a (* s q b)) s)))
 137
 138
 139 ;; Internal routines.
 140
 141 (defun pair-with-newsyms (oldforms)
 142   (let ((newsyms (mapcar (lambda (x) (make-symbol "--cl-var--")) oldforms)))
 143     (Values (mapcar* 'list newsyms oldforms) newsyms)))
 144
 145 (defun zip-lists (evens odds)
 146   (mapcan 'list evens odds))
 147
 148 (defun unzip-lists (list)
 149   (let ((e nil) (o nil))
 150     (while list
 151       (setq e (cons (car list) e) o (cons (cadr list) o) list (cddr list)))
 152     (Values (nreverse e) (nreverse o))))
 153
 154 (defun reassemble-argslists (list)
 155   (let ((n (apply 'min (mapcar 'length list))) (res nil))
 156     (while (>= (setq n (1- n)) 0)
 157       (setq res (cons (mapcar (function (lambda (x) (elt x n))) list) res)))
 158     res))
 159
 160 (defun duplicate-symbols-p (list)
 161   (let ((res nil))
 162     (while list
 163       (if (memq (car list) (cdr list)) (setq res (cons (car list) res)))
 164       (setq list (cdr list)))
 165     res))
 166
 167
 168 ;;; Setf internals.
 169
 170 (defun setnth (n list x)
 171   (setcar (nthcdr n list) x))
 172
 173 (defun setnthcdr (n list x)
 174   (setcdr (nthcdr (1- n) list) x))
 175
 176 (defun setelt (seq n x)
 177   (if (consp seq) (setcar (nthcdr n seq) x) (aset seq n x)))
 178
 179
 180 ;;; Functions omitted: case-clausify, check-do-stepforms, check-do-endforms,
 181 ;;; extract-do-inits, extract-do[*]-steps, select-stepping-forms,
 182 ;;; elt-satisfies-if[-not]-p, with-keyword-args, mv-bind-clausify,
 183 ;;; all names with embedded `$'.
 184
 185
 186 (provide 'cl-compat)
 187
 188 ;; arch-tag: 9996bb4f-aaf5-4592-b436-bf64759a3163
 189 ;;; cl-compat.el ends here