1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
;;; calc-undo.el --- undo functions for Calc -*- lexical-binding:t -*-
;; Copyright (C) 1990-1993, 2001-2021 Free Software Foundation, Inc.
;; Author: David Gillespie <daveg@synaptics.com>
;; 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 3 of the License, 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. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;;; Code:
;; This file is autoloaded from calc-ext.el.
(require 'calc-ext)
(require 'calc-macs)
;;; Undo.
;;;###autoload
(defun calc-undo (n)
(interactive "p")
(when calc-executing-macro
(error "Use C-x e, not X, to run a keyboard macro that uses Undo"))
(if (<= n 0)
(if (< n 0)
(calc-redo (- n))
(calc-last-args 1))
(calc-wrapper
(when (null (nthcdr (1- n) calc-undo-list))
(error "No further undo information available"))
(setq calc-undo-list
(prog1
(nthcdr n calc-undo-list)
(let ((saved-stack-top calc-stack-top))
(let ((calc-stack-top 0))
(calc-handle-undos calc-undo-list n))
(setq calc-stack-top saved-stack-top))))
(message "Undo!"))))
(defun calc-handle-undos (cl n)
(when (> n 0)
(let ((old-redo calc-redo-list))
(setq calc-undo-list nil)
(calc-handle-undo (car cl))
(setq calc-redo-list (append calc-undo-list old-redo)))
(calc-handle-undos (cdr cl) (1- n))))
(defun calc-handle-undo (list)
(when list
(let ((action (car list)))
(cond
((eq (car action) 'push)
(calc-pop-stack 1 (nth 1 action) t))
((eq (car action) 'pop)
(calc-push-list (nth 2 action) (nth 1 action)))
((eq (car action) 'set)
(calc-record-undo (list 'set (nth 1 action)
(symbol-value (nth 1 action))))
(set (nth 1 action) (nth 2 action)))
((eq (car action) 'store)
(let ((v (intern (nth 1 action))))
(calc-record-undo (list 'store (nth 1 action)
(and (boundp v) (symbol-value v))))
(if (y-or-n-p (format "Un-store variable %s? "
(calc-var-name (nth 1 action))))
(progn
(if (nth 2 action)
(set v (nth 2 action))
(makunbound v))
(calc-refresh-evaltos v)))))
((eq (car action) 'eval)
(calc-record-undo (append (list 'eval (nth 2 action) (nth 1 action))
(cdr (cdr (cdr action)))))
(apply (nth 1 action) (cdr (cdr (cdr action))))))
(calc-handle-undo (cdr list)))))
(defun calc-redo (n)
(interactive "p")
(when calc-executing-macro
(error "Use C-x e, not X, to run a keyboard macro that uses Redo"))
(if (<= n 0)
(calc-undo (- n))
(calc-wrapper
(when (null (nthcdr (1- n) calc-redo-list))
(error "Unable to redo"))
(setq calc-redo-list
(prog1
(nthcdr n calc-redo-list)
(let ((saved-stack-top calc-stack-top))
(let ((calc-stack-top 0))
(calc-handle-redos calc-redo-list n))
(setq calc-stack-top saved-stack-top))))
(message "Redo!"))))
(defun calc-handle-redos (cl n)
(when (> n 0)
(let ((old-undo calc-undo-list))
(setq calc-undo-list nil)
(calc-handle-undo (car cl))
(setq calc-undo-list (append calc-undo-list old-undo)))
(calc-handle-redos (cdr cl) (1- n))))
(defun calc-last-args (n)
(interactive "p")
(when calc-executing-macro
(error "Use C-x e, not X, to run a keyboard macro that uses last-args"))
(calc-wrapper
(let ((urec (calc-find-last-x calc-undo-list n)))
(if urec
(calc-handle-last-x urec)
(error "Not enough undo information available")))))
(defun calc-handle-last-x (list)
(when list
(let ((action (car list)))
(if (eq (car action) 'pop)
(calc-pop-push-record-list 0 "larg"
(delq 'top-of-stack (nth 2 action))))
(calc-handle-last-x (cdr list)))))
(defun calc-find-last-x (ul n)
(when ul
(if (calc-undo-does-pushes (car ul))
(if (<= n 1)
(car ul)
(calc-find-last-x (cdr ul) (1- n)))
(calc-find-last-x (cdr ul) n))))
(defun calc-undo-does-pushes (list)
(and list
(or (eq (car (car list)) 'pop)
(calc-undo-does-pushes (cdr list)))))
(provide 'calc-undo)
;;; calc-undo.el ends here
|
