-;;; rect.el --- rectangle functions for GNU Emacs
+;;; rect.el --- rectangle functions for GNU Emacs -*- lexical-binding:t -*-
;; Copyright (C) 1985, 1999-2013 Free Software Foundation, Inc.
(apply-on-rectangle 'rectangle-number-line-callback
start end format)))
+;;; New rectangle integration with kill-ring.
+
+;; FIXME: lots of known problems with the new rectangle support:
+;; - no key binding for mark-rectangle.
+;; - no access to the `string-rectangle' functionality.
+;; - lots of commands handle the region without paying attention to its
+;; rectangular shape.
+
+(defvar-local rectangle--region nil
+ "If non-nil, the region is meant to delimit a rectangle.")
+
+(add-hook 'deactivate-mark-hook
+ (lambda () (kill-local-variable 'rectangle--region)))
+
+(add-function :around redisplay-highlight-region-function
+ #'rectangle--highlight-for-redisplay)
+(add-function :around redisplay-unhighlight-region-function
+ #'rectangle--unhighlight-for-redisplay)
+(add-function :around region-extract-function
+ #'rectangle--extract-region)
+
+;;;###autoload
+(defun rectangle-mark ()
+ "Toggle the region as rectangular."
+ (interactive)
+ (if rectangle--region
+ (kill-local-variable 'rectangle--region)
+ (unless (region-active-p) (push-mark-command t))
+ (setq rectangle--region t)))
+
+(defun rectangle--extract-region (orig &optional delete)
+ (if (not rectangle--region)
+ (funcall orig delete)
+ (let* ((strs (funcall (if delete
+ #'delete-extract-rectangle
+ #'extract-rectangle)
+ (region-beginning) (region-end)))
+ (str (mapconcat #'identity strs "\n")))
+ (when (eq last-command 'kill-region)
+ ;; Try to prevent kill-region from appending this to some
+ ;; earlier element.
+ (setq last-command 'kill-region-dont-append))
+ (when strs
+ (put-text-property 0 (length str) 'yank-handler
+ `(rectangle--insert-for-yank ,strs t)
+ str)
+ str))))
+
+(defun rectangle--insert-for-yank (strs)
+ (push (point) buffer-undo-list)
+ (let ((undo-at-start buffer-undo-list))
+ (insert-rectangle strs)
+ (setq yank-undo-function
+ (lambda (_start _end)
+ (undo-start)
+ (setcar undo-at-start nil) ;Turn it into a boundary.
+ (while (not (eq pending-undo-list (cdr undo-at-start)))
+ (undo-more 1))))))
+
+(defun rectangle--highlight-for-redisplay (orig start end window rol)
+ (cond
+ ((not rectangle--region)
+ (funcall orig start end window rol))
+ ((and (eq 'rectangle (car-safe rol))
+ (eq (nth 1 rol) (buffer-modified-tick))
+ (eq start (nth 2 rol))
+ (eq end (nth 3 rol)))
+ rol)
+ (t
+ (save-excursion
+ (let* ((nrol nil)
+ (old (if (eq 'rectangle (car-safe rol))
+ (nthcdr 4 rol)
+ (funcall redisplay-unhighlight-region-function rol)
+ nil))
+ (ptcol (progn (goto-char start) (current-column)))
+ (markcol (progn (goto-char end) (current-column)))
+ (leftcol (min ptcol markcol))
+ (rightcol (max ptcol markcol)))
+ (goto-char start)
+ (while (< (point) end)
+ (let* ((mleft (move-to-column leftcol))
+ (left (point))
+ (mright (move-to-column rightcol))
+ (right (point))
+ (ol
+ (if (not old)
+ (let ((ol (make-overlay left right)))
+ (overlay-put ol 'window window)
+ (overlay-put ol 'face 'region)
+ ol)
+ (let ((ol (pop old)))
+ (move-overlay ol left right (current-buffer))
+ ol))))
+ ;; `move-to-column' may stop before the column (if bumping into
+ ;; EOL) or overshoot it a little, when column is in the middle
+ ;; of a char.
+ (cond
+ ((< mleft leftcol) ;`leftcol' is past EOL.
+ (overlay-put ol 'before-string
+ (spaces-string (- leftcol mleft)))
+ (setq mright (max mright leftcol)))
+ ((and (> mleft leftcol) ;`leftcol' is in the middle of a char.
+ (eq (char-before left) ?\t))
+ (setq left (1- left))
+ (move-overlay ol left right)
+ (goto-char left)
+ (overlay-put ol 'before-string
+ (spaces-string (- leftcol (current-column)))))
+ ((overlay-get ol 'before-string)
+ (overlay-put ol 'before-string nil)))
+ (cond
+ ((< mright rightcol) ;`rightcol' is past EOL.
+ (let ((str (make-string (- rightcol mright) ?\s)))
+ (put-text-property 0 (length str) 'face 'region str)
+ ;; If cursor happens to be here, draw it *before* rather than
+ ;; after this highlighted pseudo-text.
+ (put-text-property 0 1 'cursor t str)
+ (overlay-put ol 'after-string str)))
+ ((and (> mright rightcol) ;`rightcol' is in the middle of a char.
+ (eq (char-before right) ?\t))
+ (setq right (1- right))
+ (move-overlay ol left right)
+ (goto-char right)
+ (let ((str (make-string (- rightcol (current-column)) ?\s)))
+ (put-text-property 0 (length str) 'face 'region str)
+ (overlay-put ol 'after-string str)))
+ ((overlay-get ol 'after-string)
+ (overlay-put ol 'after-string nil)))
+ (when (= leftcol rightcol)
+ ;; Make zero-width rectangles visible!
+ (overlay-put ol 'after-string
+ (concat (propertize " "
+ 'face '(region (:height 0.2)))
+ (overlay-get ol 'after-string))))
+ (push ol nrol))
+ (forward-line 1))
+ (mapc #'delete-overlay old)
+ `(rectangle ,(buffer-modified-tick) ,start ,end ,@nrol))))))
+
+(defun rectangle--unhighlight-for-redisplay (orig rol)
+ (if (not (eq 'rectangle (car-safe rol)))
+ (funcall orig rol)
+ (mapc #'delete-overlay (nthcdr 4 rol))
+ (setcar (cdr rol) nil)))
+
(provide 'rect)
;;; rect.el ends here