[Gcl-devel] Problems with the 'On Lisp' development model ...

[Camm Maguire]

The following message is a courtesy copy of an article
that has been posted to comp.lang.lisp as well.

Greetings!

In the course of working with GCL and several complex applications
built atop it and shipped with Debian over the last few years, I've
increasingly realized the weaknesses of what I'm calling the 'On Lisp'
development model (after the book of the same name), and would like to
engineer some improvements.

Developers like lisp in part because everything, including the
compiler, is so well integrated.  Well, the downside of this is that
when one needs to fix something in any one layer, GCL and all its
dependent programs must be recompiled to incorporate the change.  What
looks great from a development point of view looks pretty bad from a
'shipping and maintaining working applications' point of view.

Somehow, it appears that what is needed is a lisp heap in an external
shared library, with copy-on-write pages handling the modifications,
and instructing #'save-system to write only dirty pages to disk and
properly overlay the shared lib on re-execution.  This would appear
really intractable in a copying garbage collector system -- thank
goodness this is not the case for the bulk of the GCL heap.

I'm just soliciting ideas for improvement here -- not trying to start
any sort of flame war or the like.

Take care,
-- 
Camm Maguire                                            address@hidden
==========================================================================
"The earth is but one country, and mankind its citizens."  --  Baha'u'llah