bug#46621: Copy line

[Juri Linkov]

Why there is still no such fundamental command as duplicating the current
line?  This command slightly extends the existing copy-from-above-command:

diff --git a/lisp/misc.el b/lisp/misc.el
index 09f6011f98..b3b7d8355f 100644
--- a/lisp/misc.el
+++ b/lisp/misc.el
@@ -61,6 +61,16 @@ copy-from-above-command
                                 (+ n (point)))))))
     (insert string)))
 
+;;;###autoload
+(defun copy-line (&optional arg)
+  "Duplicate the current line ARG times."
+  (interactive "p")
+  (dotimes (_ arg)
+    (forward-line 1)
+    (insert "\n")
+    (forward-line -1)
+    (copy-from-above-command)))
+
 ;; Variation of `zap-to-char'.
 
 ;;;###autoload