Re: buffer-swap-text

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Cc: emacs-devel@gnu.org
> Date: Tue, 21 Oct 2008 09:56:15 -0400
> 
> > Should this function swap the value of buffer-file-coding-system as
> > well?  Otherwise, we could confuse the user if the swapped text cannot
> > be saved with the current buffer's encoding, and we will then pop up
> > questions when the user tries to save.
> 
> I see buffer-swap-text as a (very) low-level function.  So, I'd
> rather let the code that uses it deal with things like
> buffer-file-coding-system.

I cannot imagine a situation where code that uses this function would
not want to copy buffer-file-coding-system.

> I don't think we have enough experience with it to decide whether
> that variable (or any other for that matter) needs to be swap
> alongside the buffer's text.

I'm okay with trying and erring like that, but I think that the only
reason this didn't come up yet is because the 2 sole users of this
function (tar-mode and pmail) swap text between a unibyte buffer and a
multibyte buffer, and saving is allowed only from the unibyte one (and
pmail is not yet used widely anyway).