Re: Rectangular regions

[Daniel Colascione <dancol@dancol.org>]

On 10/31/2013 11:36 AM, Jay Finger wrote:
> M-SPC is typically the chord Alt-Space, which activates the window menu
> on many systems, both X and Windows, and is consumed by the window
> manager before Emacs can get to it.  At least that's the case on the
> gnome 3.8 system I'm typing this on.  And I would not want to disable
> the binding for the window-menu as I like it's functionality and have
> many years of muscle memory for it.  So while M-SPC seems to me an
> obvious variation on C-SPC, it should probably not be the primary way to
> access this feature.
>
> I _do_ think that this should be easily accessible.  I have fond
> memories of rectangular cut/copy/paste being a first class citizen in
> the Brief text editor that I haven't used since probably '88.  So I
> would prefer as simple a chord (or sequence) as possible that still
> identifies it as being just a variation on C-SPC.
>
> So to the extent that there is a vote, I would go for either 'M-x SPC'
> or 'C-SPC C-SPC', or 'C-M-SPC'.
>
> Have you also considered, though, making rectangular regions work well
> at the elisp level?  For example, so many commands take (point mark)
> from (interactive "r") and presume to think that it's a non-rectangular
> region.  Would it be useful to have a new interactive code that instead
> supplies three arguments, (point mark shape) where shape is 'linear or
> 'rectangle.

Or better yet --- just take an interval list. An interval list would 
allow us to select a "rectangle" in bidi buffers, the underlying 
character-range chunks of which would actually be arbitrary and 
non-contiguous.