bug#64185: proposal for new function: copy-line

[Eli Zaretskii]

> From: Zachary Kanfer <zkanfer@gmail.com>
> Date: Wed, 21 Jun 2023 23:33:15 -0400
> Cc: Eshel Yaron <me@eshelyaron.com>, 64185@debbugs.gnu.org
> 
> I do think it's more useful to put point on the second line; I almost always 
> find myself wanting to edit the
> "new" line, not the old one. Yes, there isn't really a new vs old line, but I 
> write the first thing I want to see
> first, then want to duplicate it to make a changed second line.

We could have the prefix arg of - (i.e., "C-u - M-x ...") produce that
behavior from duplicate-line.  Or we could have a user option to do
that regardless of the argument, but then we should decide on which of
the N new lines to put point: the first one copied or the last one.

> I suspect that although it hasn't been in a released version yet, it's 
> slightly late to have a discussion
> about changing the behavior to leave point on the second line instead of the 
> first.

Not the default behavior, but we could have it optionally behave
differently.