bug#9054: 24.0.50; show source in other window

[Juri Linkov]

>> Done, with many other your suggestions implemented, thanks for ideas.
>
> Neat.  I would try to refine the "Select" mechanism a bit:
>
> - The order should be All>Defun>List>Line>Symbol or (preferably) the
>   inverse.

Done (but not in inverse because other apps like Gimp use such order: All>None).

> - In comments and strings it might be nice to advertise selecting the
>   entire comment or string.

This is a great idea.  I missed such ability for a long time
to be able to select the entire string.  Now this is implemented
using a new thing-at-point target 'list-or-string'.

> - Choosing All, in particular, will practically always relocate point
>   and scroll the window.  This might be confusing - many people might
>   not understand the combined effect of our "point is always visible"
>   and "point is at one end of the active region" paradigms - so we
>   should provide some way to retract that action and restore the window
>   point and start position afterwards.  Maybe None could do that by
>   default but where should List followed by Defun followed by None
>   scroll to?

Good idea, but not implementable.  This supposes that selecting All
should remember the old position of point, then None could restore it.
But what if the user selected the entire buffer with the key 'C-x h',
then selected None?