Thomas F. Burdick <tfb@conquest.OCF.Berkeley.EDU> wrote:
+---------------
| In general, I'd say the with-output-to-string approach is a
| nice compromise between making the code easy for human consumption
| and realistically optimizable.
+---------------

Especially since -- if you *do* happen to have a good guess as to
the result size -- you can provide WITH-OUTPUT-TO-STRING with an
initially-sized adjustable string to use as a starting point, as
in the example in the CLHS [slightly tweaked]:

    > (let ((string (make-array '(100) :element-type 'base-char
				       :fill-pointer 0
				       :adjustable t)))
	(with-output-to-string (s string)
	  (format s "Here's some output")
	  (format s " and some more output")
	  (format s " and some more.")
	  (format s " All done."))
	string)

    "Here's some output and some more output and some more. All done."
    > (length *)

    64
    > 


-Rob

p.s. CLHS-reading exercise for the newcomer: Why won't the following work?

      (with-output-to-string (s (make-array '(100) :element-type 'base-char
						   :fill-pointer 0
						   :adjustable t))
	(format s "Here's some output")
	(format s " and some more output")
	(format s " and some more.")
	(format s " All done."))

-----
Rob Warnock			<rpw3@rpw3.org>
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