entered into RCS

lisp/emacs-lisp/cl-compat.el

+;; cl-compat.el --- Common Lisp extensions for GNU Emacs Lisp (compatibility)
+
+;; Copyright (C) 1993 Free Software Foundation, Inc.
+
+;; Author: Dave Gillespie <daveg@synaptics.com>
+;; Version: 2.02
+;; Keywords: extensions
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs 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 1, or (at your option)
+;; any later version.
+
+;; GNU Emacs 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 GNU Emacs; see the file COPYING.  If not, write to
+;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+;; Commentary:
+
+;; These are extensions to Emacs Lisp that provide a degree of
+;; Common Lisp compatibility, beyond what is already built-in
+;; in Emacs Lisp.
+;;
+;; This package was written by Dave Gillespie; it is a complete
+;; rewrite of Cesar Quiroz's original cl.el package of December 1986.
+;;
+;; This package works with Emacs 18, Emacs 19, and Lucid Emacs 19.
+;;
+;; Bug reports, comments, and suggestions are welcome!
+
+;; This file contains emulations of internal routines of the older
+;; CL package which users may have called directly from their code.
+;; Use (require 'cl-compat) to get these routines.
+
+;; See cl.el for Change Log.
+
+
+;; Code:
+
+;; Require at load-time, but not when compiling cl-compat.
+(or (featurep 'cl) (require 'cl))
+
+
+;;; Keyword routines not supported by new package.
+
+(defmacro defkeyword (x &optional doc)
+  (list* 'defconst x (list 'quote x) (and doc (list doc))))
+
+(defun keywordp (sym)
+  (and (symbolp sym) (eq (aref (symbol-name sym) 0) ?\:) (set sym sym)))
+
+(defun keyword-of (sym)
+  (or (keywordp sym) (keywordp (intern (format ":%s" sym)))))
+
+
+;;; Multiple values.  Note that the new package uses a different
+;;; convention for multiple values.  The following definitions
+;;; emulate the old convention; all function names have been changed
+;;; by capitalizing the first letter: Values, Multiple-value-*,
+;;; to avoid conflict with the new-style definitions in cl-macs.
+
+(put 'Multiple-value-bind  'lisp-indent-function 2)
+(put 'Multiple-value-setq  'lisp-indent-function 2)
+(put 'Multiple-value-call  'lisp-indent-function 1)
+(put 'Multiple-value-prog1 'lisp-indent-function 1)
+
+(defvar *mvalues-values* nil)
+
+(defun Values (&rest val-forms)
+  (setq *mvalues-values* val-forms)
+  (car val-forms))
+
+(defun Values-list (val-forms)
+  (apply 'values val-forms))
+
+(defmacro Multiple-value-list (form)
+  (list 'let* (list '(*mvalues-values* nil) (list '*mvalues-temp* form))
+	'(or (and (eq *mvalues-temp* (car *mvalues-values*)) *mvalues-values*)
+	     (list *mvalues-temp*))))
+
+(defmacro Multiple-value-call (function &rest args)
+  (list 'apply function
+	(cons 'append
+	      (mapcar (function (lambda (x) (list 'Multiple-value-list x)))
+		      args))))
+
+(defmacro Multiple-value-bind (vars form &rest body)
+  (list* 'multiple-value-bind vars (list 'Multiple-value-list form) body))
+
+(defmacro Multiple-value-setq (vars form)
+  (list 'multiple-value-setq vars (list 'Multiple-value-list form)))
+
+(defmacro Multiple-value-prog1 (form &rest body)
+  (list 'prog1 form (list* 'let '((*mvalues-values* nil)) body)))
+
+
+;;; Routines for parsing keyword arguments.
+
+(defun build-klist (arglist keys &optional allow-others)
+  (let ((res (Multiple-value-call 'mapcar* 'cons (unzip-lists arglist))))
+    (or allow-others
+	(let ((bad (set-difference (mapcar 'car res) keys)))
+	  (if bad (error "Bad keywords: %s not in %s" bad keys))))
+    res))
+
+(defun extract-from-klist (klist key &optional def)
+  (let ((res (assq key klist))) (if res (cdr res) def)))
+
+(defun keyword-argument-supplied-p (klist key)
+  (assq key klist))
+
+(defun elt-satisfies-test-p (item elt klist)
+  (let ((test-not (cdr (assq ':test-not klist)))
+	(test (cdr (assq ':test klist)))
+	(key (cdr (assq ':key klist))))
+    (if key (setq elt (funcall key elt)))
+    (if test-not (not (funcall test-not item elt))
+      (funcall (or test 'eql) item elt))))
+
+
+;;; Rounding functions with old-style multiple value returns.
+
+(defun cl-floor (a &optional b) (Values-list (floor* a b)))
+(defun cl-ceiling (a &optional b) (Values-list (ceiling* a b)))
+(defun cl-round (a &optional b) (Values-list (round* a b)))
+(defun cl-truncate (a &optional b) (Values-list (truncate* a b)))
+
+(defun safe-idiv (a b)
+  (let* ((q (/ (abs a) (abs b)))
+         (s (* (signum a) (signum b))))
+    (Values q (- a (* s q b)) s)))
+
+
+;; Internal routines.
+
+(defun pair-with-newsyms (oldforms)
+  (let ((newsyms (mapcar (function (lambda (x) (gensym))) oldforms)))
+    (Values (mapcar* 'list newsyms oldforms) newsyms)))
+
+(defun zip-lists (evens odds)
+  (mapcan 'list evens odds))
+
+(defun unzip-lists (list)
+  (let ((e nil) (o nil))
+    (while list
+      (setq e (cons (car list) e) o (cons (cadr list) o) list (cddr list)))
+    (Values (nreverse e) (nreverse o))))
+
+(defun reassemble-argslists (list)
+  (let ((n (apply 'min (mapcar 'length list))) (res nil))
+    (while (>= (setq n (1- n)) 0)
+      (setq res (cons (mapcar (function (lambda (x) (elt x n))) list) res)))
+    res))
+
+(defun duplicate-symbols-p (list)
+  (let ((res nil))
+    (while list
+      (if (memq (car list) (cdr list)) (setq res (cons (car list) res)))
+      (setq list (cdr list)))
+    res))
+
+
+;;; Setf internals.
+
+(defun setnth (n list x)
+  (setcar (nthcdr n list) x))
+
+(defun setnthcdr (n list x)
+  (setcdr (nthcdr (1- n) list) x))
+
+(defun setelt (seq n x)
+  (if (consp seq) (setcar (nthcdr n seq) x) (aset seq n x)))
+
+
+;;; Functions omitted: case-clausify, check-do-stepforms, check-do-endforms,
+;;; extract-do-inits, extract-do[*]-steps, select-stepping-forms,
+;;; elt-satisfies-if[-not]-p, with-keyword-args, mv-bind-clausify,
+;;; all names with embedded `$'.
+
+
+(provide 'cl-compat)
+
+;;; cl-compat.el ends here
+