lisp/register.el

   1 ;; Register commands for Emacs.
   2 ;; Copyright (C) 1985 Free Software Foundation, Inc.
   3
   4 ;; This file is part of GNU Emacs.
   5
   6 ;; GNU Emacs is free software; you can redistribute it and/or modify
   7 ;; it under the terms of the GNU General Public License as published by
   8 ;; the Free Software Foundation; either version 1, or (at your option)
   9 ;; any later version.
  10
  11 ;; GNU Emacs is distributed in the hope that it will be useful,
  12 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;; GNU General Public License for more details.
  15
  16 ;; You should have received a copy of the GNU General Public License
  17 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  18 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20
  21 (defvar register-alist nil
  22   "Alist of elements (NAME . CONTENTS), one for each Emacs register.
  23 NAME is a character (a number).  CONTENTS is a string, number,
  24 mark or list.  A list represents a rectangle; its elements are strings.")
  25
  26 (defun get-register (char)
  27   "Return contents of Emacs register named CHAR, or nil if none."
  28   (cdr (assq char register-alist)))
  29
  30 (defun set-register (char value)
  31   "Set contents of Emacs register named CHAR to VALUE.
  32 Returns VALUE."
  33   (let ((aelt (assq char register-alist)))
  34     (if aelt
  35         (setcdr aelt value)
  36       (setq aelt (cons char value))
  37       (setq register-alist (cons aelt register-alist)))
  38     value))
  39
  40 (defun point-to-register (char)
  41   "Store current location of point in a register.
  42 Argument is a character, naming the register."
  43   (interactive "cPoint to register: ")
  44   (set-register char (point-marker)))
  45
  46 (fset 'register-to-point 'jump-to-register)
  47 (defun jump-to-register (char)
  48   "Move point to location stored in a register.
  49 Argument is a character, naming the register."
  50   (interactive "cJump to register: ")
  51   (let ((val (get-register char)))
  52     (if (markerp val)
  53         (progn
  54           (switch-to-buffer (marker-buffer val))
  55           (goto-char val))
  56       (error "Register doesn't contain a buffer position"))))
  57
  58 ;(defun number-to-register (arg char)
  59 ;  "Store a number in a register.
  60 ;Two args, NUMBER and REGISTER (a character, naming the register).
  61 ;If NUMBER is nil, digits in the buffer following point are read
  62 ;to get the number to store.
  63 ;Interactively, NUMBER is the prefix arg (none means nil)."
  64 ;  (interactive "P\ncNumber to register: ")
  65 ;  (set-register char
  66 ;               (if arg
  67 ;                   (prefix-numeric-value arg)
  68 ;                 (if (looking-at "[0-9][0-9]*")
  69 ;                     (save-excursion
  70 ;                      (save-restriction
  71 ;                       (narrow-to-region (point)
  72 ;                                         (progn (skip-chars-forward "0-9")
  73 ;                                                (point)))
  74 ;                       (goto-char (point-min))
  75 ;                       (read (current-buffer))))
  76 ;                   0))))
  77
  78 ;(defun increment-register (arg char)
  79 ;  "Add NUMBER to the contents of register REGISTER.
  80 ;Interactively, NUMBER is the prefix arg (none means nil)."
  81 ;  (interactive "p\ncNumber to register: ")
  82 ;  (or (integerp (get-register char))
  83 ;      (error "Register does not contain a number"))
  84 ;  (set-register char (+ arg (get-register char))))
  85
  86 (defun view-register (char)
  87   "Display what is contained in register named REGISTER.
  88 REGISTER is a character."
  89   (interactive "cView register: ")
  90   (let ((val (get-register char)))
  91     (if (null val)
  92         (message "Register %s is empty" (single-key-description char))
  93       (with-output-to-temp-buffer "*Output*"
  94         (princ "Register ")
  95         (princ (single-key-description char))
  96         (princ " contains ")
  97         (if (integerp val)
  98             (princ val)
  99           (if (markerp val)
 100               (progn
 101                 (princ "a buffer position:\nbuffer ")
 102                 (princ (buffer-name (marker-buffer val)))
 103                 (princ ", position ")
 104                 (princ (+ 0 val)))
 105             (if (consp val)
 106                 (progn
 107                   (princ "the rectangle:\n")
 108                   (while val
 109                     (princ (car val))
 110                     (terpri)
 111                     (setq val (cdr val))))
 112               (princ "the string:\n")
 113               (princ val))))))))
 114
 115 (defun insert-register (char &optional arg)
 116   "Insert contents of register REG.  REG is a character.
 117 Normally puts point before and mark after the inserted text.
 118 If optional second arg is non-nil, puts mark before and point after.
 119 Interactively, second arg is non-nil if prefix arg is supplied."
 120   (interactive "cInsert register: \nP")
 121   (push-mark)
 122   (let ((val (get-register char)))
 123     (if (consp val)
 124         (insert-rectangle val)
 125       (if (stringp val)
 126           (insert val)
 127         (if (or (integerp val) (markerp val))
 128             (princ (+ 0 val) (current-buffer))
 129           (error "Register does not contain text")))))
 130   (if (not arg) (exchange-point-and-mark)))
 131
 132 (defun copy-to-register (char start end &optional delete-flag)
 133   "Copy region into register REG.
 134 With prefix arg, delete as well.
 135 Called from program, takes four args:
 136 REG, START, END and DELETE-FLAG.
 137 START and END are buffer positions indicating what to copy."
 138   (interactive "cCopy to register: \nr\nP")
 139   (set-register char (buffer-substring start end))
 140   (if delete-flag (delete-region start end)))
 141
 142 (defun append-to-register (char start end &optional delete-flag)
 143   "Append region to text in register REG.
 144 With prefix arg, delete as well.
 145 Called from program, takes four args:
 146 REG, START, END and DELETE-FLAG.
 147 START and END are buffer positions indicating what to append."
 148   (interactive "cAppend to register: \nr\nP")
 149   (or (stringp (get-register char))
 150       (error "Register does not contain text"))
 151   (set-register char (concat (get-register char)
 152                              (buffer-substring start end)))
 153   (if delete-flag (delete-region start end)))
 154
 155 (defun prepend-to-register (char start end &optional delete-flag)
 156   "Prepend region to text in register REG.
 157 With prefix arg, delete as well.
 158 Called from program, takes four args:
 159 REG, START, END and DELETE-FLAG.
 160 START and END are buffer positions indicating what to prepend."
 161   (interactive "cPrepend to register: \nr\nP")
 162   (or (stringp (get-register char))
 163       (error "Register does not contain text"))
 164   (set-register char (concat (buffer-substring start end)
 165                              (get-register char)))
 166   (if delete-flag (delete-region start end)))
 167
 168 (defun copy-rectangle-to-register (char start end &optional delete-flag)
 169   "Copy rectangular region into register REG.
 170 With prefix arg, delete as well.
 171 Called from program, takes four args:
 172 REG, START, END and DELETE-FLAG.
 173 START and END are buffer positions giving two corners of rectangle."
 174   (interactive "cCopy rectangle to register: \nr\nP")
 175   (set-register char
 176                 (if delete-flag
 177                     (delete-extract-rectangle start end)
 178                   (extract-rectangle start end))))