On Sat, Aug 11, 2012 at 3:27 AM, Stefan Monnier <monnier@iro.umontreal.ca>wrote:

> > Aplus (a gnu/linux APL variant) has been one of the languages that
> > runs only on XEmacs but not GNU-Emacs.  Recently XEmacs has been
> > giving some trouble compiling under Debian (it seems).
> > I have hacked up something which makes Aplus run with GNU-Emacs:
> > http://www.emacswiki.org/emacs/AplInDebian
> > Is this a suitable forum for discussions towards cleaning up that code?
>
> Sure.  Especially if you intend to include it in GNU ELPA.
> Since Markus has already signed the needed copyright paperwork,
> and it doesn't look like the code has seen many external contributions,
> inclusion in GNU ELPA should be fairly easy.
>
> As for cleaning up the code, I suggest you start by defining a major
> mode for APL code.  See sample-mode.el for an example.
> This mode would most likely enable the apl input method by default.
>

Ive defined inferior-apl-mode by copying from cmu-scheme like this:

(define-derived-mode inferior-apl-mode comint-mode "Inferior APL" ....

and then removing most of the stuff to keep it still working.

The current version at http://www.emacswiki.org/emacs/inferior-apl.el
is a still further cleaned up and cut-down version.
Of course the mode-ly stuff should be cleaned up -- I dont understand the
scoping rules for buffer-local variables.

I think however that there are more immediate questions before that.

The code was up there on the wiki and working as best as I knew until
someone informed me that it was not.  The immediate hack I found was that
starting emacs with
LANG=C makes it again work.  Evidently when the OS moved from defaulting to
latin-1 to utf-8 this broke.

Trying to make an 'inside-emacs' version of the same hack I discovered that
the following does the trick of removing the need for LANG=C.

(setq coding-system-for-write 'iso-latin-1)
(setq coding-system-for-read 'iso-latin-1)

Obviously this is not a proper solution.
Firstly these variables should not be globally assigned.  Whats the best
way of scoping these assignments or should some other variables be used I
am not sure.

The second point is that iso-latin-1 just works by saying so-to-speak
"Not-UTF" but it is obviously wrong.

So in short: How do I say "latinish" without saying latin-1.  And where
(scope) to say it?

Perhaps the best solution would be to define a new Aplus charset.
The tables are already there in Markus code.  Maybe just some tying some
ends together required?  Any pointers/docs on how one goes about converting
a restricted-charset-to-unicode data-table into an emacs charset?

Thanks

Rusi