From: Thaddeus L Olczyk
Subject: Checkpointing a lisp session.
Date: 
Message-ID: <3c72366c.235426187@nntp.interaccess.com>
I'm working on something where a large data set is generated for
processing ( to be more precise there will be a very large data set
for the real run, for testing there is a large data set, the data set
takes a couple hours to generate ).

Initially it takes no time to test things, but after pounding on
things for a while the debug-edit-run cycle just gets very large.

What I would like to do is something like:
in file "presently-working.lisp"

(defun function-that-I-am-writing-and-or debugging-now(x y z)
    (stuff-I'm-sure-works)
     ....
     (save-checkpoint first-checkpoint)
     ( stuff-I-will-be tweaking)
)

-----------------------------------
in "test-file.lisp"

;; Load ltest tweak.
(load "presently-working.lisp")
(resume first-checkpoint)

-----------------------------------

In other languages, I don't think doint this is possible, but I think
there may be a way of doing this in lisp.
Suggestions?
PS I'm using clisp, I'm also assuming that loading
presently-working.lisp does not have side effects other
then defining a few basic things (functions, classes).
In particular it does not reset any global variables.