The recent discussion of optimizing Lisp with number has been quite
interesting. One question I had about CMUCL I don't think got
answered. In Allegro Lisp, I believe it's the case that local
functions can return numbers without fear that they'll be boxed:
(labels ((nfn () ...))
(cond (...)
(t (sqrt (nfn ...)))))
I don't know if any declarations are required, but the idea is that
even if nfn returns a double-float, the compiler can figure out that
it doesn't need to box it when passing it to sqrt. (Of course, all
bets are off if we do something like (setq global-var* #'nfn).)
Is this also true for CMUCL? If so, it's another way to cope besides
inlining and block compiling. (Not always applicable, I realize, if
you really do need to call nfn in more than one function).
--
-- Drew McDermott
Yale University
Computer Science Department
