Re: Bringing up a new PCL

[Gregor.pa@Xerox.COM]

    Date: Fri, 9 Dec 88 13:47:51 EST
    From: Arun Welch <welch@cis.ohio-state.edu>


    Does anyone have any feel for what it takes to bring up PCL starting
    from a pure CL and the files on arisia as they stand now? In other
    words, if I had a CL, and wanted PCL/CLOS, how many man-months would
    it be to get it?  

It depends on the Common Lisp in question of course.  Given a reasonably
debugged Common Lisp I believe I can make a PCL port to it in under two
days.  If the Common Lisp has a lot of bugs, or is just generally slow,
it could take longer of course.
		      
		      How much is involved in tracking the moving CLOS
    target?

I am not sure I understand this question, so let me reword it and answer
that question.

 Once I have this port of PCL, how much work will I have to do to
 maintain it as PCL evolves to conform to the standard?

Very little.  Maybe 1 or 2 weeks total.  If on the other hand, you also
want to take advantage of the changes that will be made to PCL to make
it have higher performance that will take more work.  Depending on how
much of the performance you want to get, and depending on the
architecture of your Lisp, this could take from 1 to 3 months.

Then there is the time it would take to really retrofit PCL to be a
super high performance CLOS implementation in your Lisp.  I can't begin
to estimate how much work that would take.
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