Initial revision

lisp/register.el

+;; Register commands for Emacs.
+;; Copyright (C) 1985 Free Software Foundation, Inc.
+
+;; 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.
+
+
+(defvar register-alist nil
+  "Alist of elements (NAME . CONTENTS), one for each Emacs register.
+NAME is a character (a number).  CONTENTS is a string, number,
+mark or list.  A list represents a rectangle; its elements are strings.")
+
+(defun get-register (char)
+  "Return contents of Emacs register named CHAR, or nil if none."
+  (cdr (assq char register-alist)))
+
+(defun set-register (char value)
+  "Set contents of Emacs register named CHAR to VALUE.
+Returns VALUE."
+  (let ((aelt (assq char register-alist)))
+    (if aelt
+	(setcdr aelt value)
+      (setq aelt (cons char value))
+      (setq register-alist (cons aelt register-alist)))
+    value))
+
+(defun point-to-register (char)
+  "Store current location of point in a register.
+Argument is a character, naming the register."
+  (interactive "cPoint to register: ")
+  (set-register char (point-marker)))
+
+(fset 'register-to-point 'jump-to-register)
+(defun jump-to-register (char)
+  "Move point to location stored in a register.
+Argument is a character, naming the register."
+  (interactive "cJump to register: ")
+  (let ((val (get-register char)))
+    (if (markerp val)
+	(progn
+	  (switch-to-buffer (marker-buffer val))
+	  (goto-char val))
+      (error "Register doesn't contain a buffer position"))))
+
+;(defun number-to-register (arg char)
+;  "Store a number in a register.
+;Two args, NUMBER and REGISTER (a character, naming the register).
+;If NUMBER is nil, digits in the buffer following point are read
+;to get the number to store.
+;Interactively, NUMBER is the prefix arg (none means nil)."
+;  (interactive "P\ncNumber to register: ")
+;  (set-register char 
+;		(if arg
+;		    (prefix-numeric-value arg)
+;		  (if (looking-at "[0-9][0-9]*")
+;		      (save-excursion
+;		       (save-restriction
+;			(narrow-to-region (point)
+;					  (progn (skip-chars-forward "0-9")
+;						 (point)))
+;			(goto-char (point-min))
+;			(read (current-buffer))))
+;		    0))))
+
+;(defun increment-register (arg char)
+;  "Add NUMBER to the contents of register REGISTER.
+;Interactively, NUMBER is the prefix arg (none means nil)." 
+;  (interactive "p\ncNumber to register: ")
+;  (or (integerp (get-register char))
+;      (error "Register does not contain a number"))
+;  (set-register char (+ arg (get-register char))))
+
+(defun view-register (char)
+  "Display what is contained in register named REGISTER.
+REGISTER is a character."
+  (interactive "cView register: ")
+  (let ((val (get-register char)))
+    (if (null val)
+	(message "Register %s is empty" (single-key-description char))
+      (with-output-to-temp-buffer "*Output*"
+	(princ "Register ")
+	(princ (single-key-description char))
+	(princ " contains ")
+	(if (integerp val)
+	    (princ val)
+	  (if (markerp val)
+	      (progn
+		(princ "a buffer position:\nbuffer ")
+		(princ (buffer-name (marker-buffer val)))
+		(princ ", position ")
+		(princ (+ 0 val)))
+	    (if (consp val)
+		(progn
+		  (princ "the rectangle:\n")
+		  (setq val (cdr val))
+		  (while val
+		    (princ (car val))
+		    (terpri)
+		    (setq val (cdr val))))
+	      (princ "the string:\n")
+	      (princ val))))))))
+
+(defun insert-register (char &optional arg)
+  "Insert contents of register REG.  REG is a character.
+Normally puts point before and mark after the inserted text.
+If optional second arg is non-nil, puts mark before and point after.
+Interactively, second arg is non-nil if prefix arg is supplied."
+  (interactive "cInsert register: \nP")
+  (push-mark)
+  (let ((val (get-register char)))
+    (if (consp val)
+	(insert-rectangle val)
+      (if (stringp val)
+	  (insert val)
+	(if (or (integerp val) (markerp val))
+	    (princ (+ 0 val) (current-buffer))
+	  (error "Register does not contain text")))))
+  (if (not arg) (exchange-point-and-mark)))
+
+(defun copy-to-register (char start end &optional delete-flag)
+  "Copy region into register REG.
+With prefix arg, delete as well.
+Called from program, takes four args:
+REG, START, END and DELETE-FLAG.
+START and END are buffer positions indicating what to copy."
+  (interactive "cCopy to register: \nr\nP")
+  (set-register char (buffer-substring start end))
+  (if delete-flag (delete-region start end)))
+
+(defun append-to-register (char start end &optional delete-flag)
+  "Append region to text in register REG.
+With prefix arg, delete as well.
+Called from program, takes four args:
+REG, START, END and DELETE-FLAG.
+START and END are buffer positions indicating what to append."
+  (interactive "cAppend to register: \nr\nP")
+  (or (stringp (get-register char))
+      (error "Register does not contain text"))
+  (set-register char (concat (get-register char)
+			     (buffer-substring start end)))
+  (if delete-flag (delete-region start end)))
+
+(defun prepend-to-register (char start end &optional delete-flag)
+  "Prepend region to text in register REG.
+With prefix arg, delete as well.
+Called from program, takes four args:
+REG, START, END and DELETE-FLAG.
+START and END are buffer positions indicating what to prepend."
+  (interactive "cPrepend to register: \nr\nP")
+  (or (stringp (get-register char))
+      (error "Register does not contain text"))
+  (set-register char (concat (buffer-substring start end)
+			     (get-register char)))
+  (if delete-flag (delete-region start end)))
+
+(defun copy-rectangle-to-register (char start end &optional delete-flag)
+  "Copy rectangular region into register REG.
+With prefix arg, delete as well.
+Called from program, takes four args:
+REG, START, END and DELETE-FLAG.
+START and END are buffer positions giving two corners of rectangle."
+  (interactive "cCopy rectangle to register: \nr\nP")
+  (set-register char
+		(if delete-flag
+		    (delete-extract-rectangle start end)
+		  (extract-rectangle start end))))