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[jinx@CHAMARTIN.AI.MIT.EDU: Extending the address space of MIT Cscheme (long reply)]

re: The sad fact of life is that most of the Lisp community does not care
    about numeric code, and the few exceptions in the community are rare
    and seen as odd birds.  The only widespread Lisp compiler that has
    provided good performance (MacLisp) required (from what I've heard)
    over 10 man-years of implementation (by JONL, you (GLS), and others).

Ah, 10 man-years!  [really, I don't think it was that much for MacLisp,
but it certainly wasn't a sophmore's term project].

The sadder fact is how often, during the past 30 years of Lisp existence,
that the total cost of producing a high-quality compiler and system has 
been grossly underestimated.  At least one world-class company in Germany 
is reported to have embarked on a Common Lisp effort with an adequate 
understanding of the level of effort required.   But that's just about 
the only one I know of; almost every other case I'm aware of is off -- on 
the low side -- by a factor of two or more.

Say, didn't Chris mention about 10 man-years of development on CScheme,
and still not much of a compiler yet?  Applause for his candor.

A few Lisp efforts took someone else's working, and highly portable,
Lisp compiler and produced from that a working Lisp compiler for their
operating-system/machine.  Ocasionally I've heard someone publicly boast
that he wrote "the compiler" in well under a man-year, when in fact I know
it to be a case like this.  But even this piggy-backing of compilers is a 
job whose level of effort is often underestimated.

-- JonL --

P.S.  I'd like to throw in the name Rod Brooks -- although he isn't one of
      the "others" you mention above, he was a principal on the S1 Lisp
      development, and he is (I would say) the principal developer of the
      Lucid compiler.  If Quux and I et. al. are odd birds, then so is Rod.