1 files changed, 40 insertions, 0 deletions
diff --git a/lisp/rect.el b/lisp/rect.el
index ba13e123580..6b6906ac893 100644
--- a/lisp/rect.el
+++ b/lisp/rect.el
@@ -167,6 +167,45 @@ The final point after the last operation will be returned."
                  (<= (point) endpt))))
       final-point)))
 
+(defun rectangle-position-as-coordinates (position)
+   "Return cons of the column and line values of POSITION.
+POSITION specifies a position of the current buffer.  The value
+returned has the form (COLUMN . LINE)."
+  (save-excursion
+    (goto-char position)
+    (let ((col (current-column))
+          (line (line-number-at-pos)))
+      (cons col line))))
+
+(defun rectangle-intersect-p (pos1 size1 pos2 size2)
+   "Return non-nil if two rectangles intersect.
+POS1 and POS2 specify the positions of the upper-left corners of
+the first and second rectangles as conses of the form (COLUMN . LINE).
+SIZE1 and SIZE2 specify the dimensions of the first and second
+rectangles, as conses of the form (WIDTH . HEIGHT)."
+  (let ((x1 (car pos1))
+        (y1 (cdr pos1))
+        (x2 (car pos2))
+        (y2 (cdr pos2))
+        (w1 (car size1))
+        (h1 (cdr size1))
+        (w2 (car size2))
+        (h2 (cdr size2)))
+    (not (or (<= (+ x1 w1) x2)
+             (<= (+ x2 w2) x1)
+             (<= (+ y1 h1) y2)
+             (<= (+ y2 h2) y1)))))
+
+(defun rectangle-dimensions (start end)
+  "Return the dimensions of the rectangle with corners at START
+and END. The returned value has the form of (WIDTH . HEIGHT)."
+  (save-excursion
+    (let* ((height (1+ (abs (- (line-number-at-pos end)
+                               (line-number-at-pos start)))))
+           (cols (rectangle--pos-cols start end))
+           (width (abs (- (cdr cols) (car cols)))))
+      (cons width height))))
+
 (defun delete-rectangle-line (startcol endcol fill)
   (when (= (move-to-column startcol (if fill t 'coerce)) startcol)
     (delete-region (point)
@@ -604,6 +643,7 @@ with a prefix argument, prompt for START-AT and FORMAT."
 ;;;###autoload
 (define-minor-mode rectangle-mark-mode
   "Toggle the region as rectangular.
+
 Activates the region if needed.  Only lasts until the region is deactivated."
   nil nil nil
   (rectangle--reset-crutches)