Re: Emacs rewrite in a maintainable language

[Marcin Borkowski <mbork@mbork.pl>]

On 2015-10-12, at 10:12, Steinar Bang <sb@dod.no> wrote:

>>>>>> Paul Eggert <eggert@cs.ucla.edu>:
>
>> The TIOBE Index isn't a perfect measure, of course. And I am not
>> advocating that we rewrite the Emacs core in Java.
>
> (FWIW it's already been done once, but the project doesn't seem to have
> been touched for a decade... http://jemacs.sourceforge.net/ (unless it
> has moved to a new home...? I found a 4 year old fork on github, but it hasn't
> preserved the old jemacs history, so it is hard to see what it
> adds... also the last commit was 4 years ago https://github.com/shadgregory/JEmacs ))

For the record: there was once a project to rewrite TeX in Java (it was
before the mankind learned that Java was not the solution to all the
humanity's problems).  It even got some funding (as in, real money).
The project is now considered a failure: while they /did/ produce
a working, 99.9% compatible TeX replacement, it was an order of
magnitude slower (or so), and the main goal - to have a TeX replacement
written in a more modular fashion, so that it would be easier to
e.g. experiment with various line/page-breaking algorithms and
extensions to TeX - was not achieved: nobody actually performed those
experiments.  (There aren't even many traces on the internet; while you
can read about this "New Typesetting System" in a few places, the actual
code is lost.  That is a pity, imho, since I hear that Java is much
faster nowadays than 10+ years ago, so it might work now.)

Another project, LuaTeX, took off and can be now considered very
successful.  This project, however, has different goals (instead of
replacing TeX with something different, they embedded Lua in TeX, and
then opend up a possibility to reimplement many parts of TeX in Lua.  In
effect, it seems that the goal of NTS - to be able to easily experiment
with TeX internals - was achieved, though in a completely different
way).  Also, it is run by a small group of dedicated individuals, and my
guess is that one of the reasons of its success is Hans Hagen and his
team.  One, they are exceptionally smart people.  Two, they /think/ and
/design/ before coding, not the other way round.  (Not to say that Emacs
devs don't do it, but the majority of the software world apparently got
this wrong.)  Last but not least, Hans' company is based around ConTeXt
and LuaTeX, so he has a /really/ strong motivation to have this system
working smoothly: he /actually relies on it for his income/.

Best,

-- 
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Faculty of Mathematics and Computer Science
Adam Mickiewicz University