Re: Emacs rewrite in a maintainable language

[Stephen J. Turnbull]

David Kastrup writes:

 > My personal opinion is that It's unlikely to survive into GuileEmacs for
 > mostly technical reasons.  The best one could do is make it stick when a
 > module calls Emacs-specific functionality.  But if it uses the general
 > GUILE stuff (namely could be called from a standard GUILE interpreter),
 > Emacs cannot really make a licensing claim that sticks.

[David pointed this out elsewhere, but I want to emphasize: GUILE
distributed as a part of Emacs is GPL, not LGPL, and the protection of
the GPL extends to all code in the Emacs process space.  GuileEmacs
can be distributed only because the LGPL allows promotion to GPL.]

If you're just referring to the fact that any code that doesn't work
with buffers or call Emacs redisplay etc can be licensed as you like,
sure.  But that's always true anyway.  If the module is written in
GUILE Scheme or via GUILE FFI with the intention that its input or
output be Emacs-specific, however, it becomes a derivative of Emacs,
and the GPL applies just as it would with "native" Emacs modules.
Proving that in court might be sticky, but I don't think it would stop
RMS from insisting on a "I'm GPL" API in GuileEmacs distributed by
GNU, and making downstream make any decision about allowing broader
modules (and perhaps suffer an FSF legal action if RMS believes that
appropriate).

What might give RMS pause would be the prospect of forking GUILE to
add such an API.

 > > I'm not panicking.  GuileEmacs has zero attraction for me *personally*
 > > because on the one hand its advocates admit it still needs work.  On
 > > the other none of its claimed advantages excite *me* one bit.
 > 
 > I like arbitrary precision integers and rationals and the whole numeric
 > stack.

I have those. ;-)  (Joke because XEmacs doesn't have a true numeric
tower.  SXEmacs may have made progress in that direction, though.)

 > I also like the availability of applications and libraries that
 > have not been written specifically for Emacs: replacing much of the
 > backend behind Emacs Calc with native Jacal would be an interesting
 > feat, and there are a number of other pathways opening up.

Indeed interesting, although these days I'd be more interested in
numpy and numba.  But I agree with your word "feat"; I'd be surprised
when it happened; I suspect Jay Belanger isn't so interested in that.
Maybe he'll speak up.

 > Elisp is not used for creating scripts to any serious degree, the
 > existence of rep notwithstanding (show of hands: which Emacs developer
 > ever worked with rep or even knows it?).

Isn't that the engine in the sawfish WM?  <raises limb="arm"/>

 > GUILE can (and will) be used for scripting.  So for GNU integration
 > and desktop cohesion, this may be a strategical step.

Agreed that's very interesting and *will* happen (but *my* desktop is
Mac OS X, hate GNOME 3, hate hate hate hate ;-) -- of course it would
be very cool for GNOME users, and there are many happy GNOME users).

 > So I do see longterm goals and strategies that could be opened by a good
 > integration of GUILE as a core part of Emacs.

Sure.  I just don't see them *for me* and *right now*.

 > The most relevant obstacle _will_ be to overcome the "don't mess
 > with my project" stance in both Emacs and GUILE from people that
 > have come to like the respective culture and environment of the
 > isolated projects.

Most likely. :-(  But if it really looks like a great idea, RMS will
come and threaten to knock heads, and that will be all it takes for
all to turn sweetness and light (you and me excepted, of course ;-).