1 ;;; calc-undo.el --- undo functions for Calc
3 ;; Copyright (C) 1990-1993, 2001-2015 Free Software Foundation, Inc.
5 ;; Author: David Gillespie <daveg@synaptics.com>
6 ;; Maintainer: Jay Belanger <jay.p.belanger@gmail.com>
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software: you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation, either version 3 of the License, or
13 ;; (at your option) any later version.
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
27 ;; This file is autoloaded from calc-ext.el.
37 (when calc-executing-macro
38 (error "Use C-x e, not X, to run a keyboard macro that uses Undo"))
44 (when (null (nthcdr (1- n) calc-undo-list))
45 (error "No further undo information available"))
48 (nthcdr n calc-undo-list)
49 (let ((saved-stack-top calc-stack-top))
50 (let ((calc-stack-top 0))
51 (calc-handle-undos calc-undo-list n))
52 (setq calc-stack-top saved-stack-top))))
55 (defun calc-handle-undos (cl n)
57 (let ((old-redo calc-redo-list))
58 (setq calc-undo-list nil)
59 (calc-handle-undo (car cl))
60 (setq calc-redo-list (append calc-undo-list old-redo)))
61 (calc-handle-undos (cdr cl) (1- n))))
63 (defun calc-handle-undo (list)
65 (let ((action (car list)))
67 ((eq (car action) 'push)
68 (calc-pop-stack 1 (nth 1 action) t))
69 ((eq (car action) 'pop)
70 (calc-push-list (nth 2 action) (nth 1 action)))
71 ((eq (car action) 'set)
72 (calc-record-undo (list 'set (nth 1 action)
73 (symbol-value (nth 1 action))))
74 (set (nth 1 action) (nth 2 action)))
75 ((eq (car action) 'store)
76 (let ((v (intern (nth 1 action))))
77 (calc-record-undo (list 'store (nth 1 action)
78 (and (boundp v) (symbol-value v))))
79 (if (y-or-n-p (format "Un-store variable %s? "
80 (calc-var-name (nth 1 action))))
83 (set v (nth 2 action))
85 (calc-refresh-evaltos v)))))
86 ((eq (car action) 'eval)
87 (calc-record-undo (append (list 'eval (nth 2 action) (nth 1 action))
88 (cdr (cdr (cdr action)))))
89 (apply (nth 1 action) (cdr (cdr (cdr action))))))
90 (calc-handle-undo (cdr list)))))
94 (when calc-executing-macro
95 (error "Use C-x e, not X, to run a keyboard macro that uses Redo"))
99 (when (null (nthcdr (1- n) calc-redo-list))
100 (error "Unable to redo"))
103 (nthcdr n calc-redo-list)
104 (let ((saved-stack-top calc-stack-top))
105 (let ((calc-stack-top 0))
106 (calc-handle-redos calc-redo-list n))
107 (setq calc-stack-top saved-stack-top))))
110 (defun calc-handle-redos (cl n)
112 (let ((old-undo calc-undo-list))
113 (setq calc-undo-list nil)
114 (calc-handle-undo (car cl))
115 (setq calc-undo-list (append calc-undo-list old-undo)))
116 (calc-handle-redos (cdr cl) (1- n))))
118 (defun calc-last-args (n)
120 (when calc-executing-macro
121 (error "Use C-x e, not X, to run a keyboard macro that uses last-args"))
123 (let ((urec (calc-find-last-x calc-undo-list n)))
125 (calc-handle-last-x urec)
126 (error "Not enough undo information available")))))
128 (defun calc-handle-last-x (list)
130 (let ((action (car list)))
131 (if (eq (car action) 'pop)
132 (calc-pop-push-record-list 0 "larg"
133 (delq 'top-of-stack (nth 2 action))))
134 (calc-handle-last-x (cdr list)))))
136 (defun calc-find-last-x (ul n)
138 (if (calc-undo-does-pushes (car ul))
141 (calc-find-last-x (cdr ul) (1- n)))
142 (calc-find-last-x (cdr ul) n))))
144 (defun calc-undo-does-pushes (list)
146 (or (eq (car (car list)) 'pop)
147 (calc-undo-does-pushes (cdr list)))))
151 ;;; calc-undo.el ends here