Re: sanity check (coding style)

tar@xxxxxxxxxxxxx (Thomas A. Russ) writes:

> Christophe Rhodes <csr21@xxxxxxxxx> writes:
>
> (defun digest2string (v)
> (with-output-to-string (s)
> (loop for x across v
> do (format s "~2,'0X" x))))
>
>
> This is nice, since it uses the string stream to collect the values. If
> efficiency is really critical, one could avoid the FORMAT call (which
> often tends to be slow) and subsitute a 256 element lookup table:
>
> (defconstant *hex-codes* #("00" "01" ... "FF"))

Surely we don't have to write that by hand; that's not The Lisp Way!

(defconstant *hex-codes* #.(coerce (loop for i from #x00 to #xff collect (format nil "~2,'0x" i)) 'vector))

;-)

-Peter

--
Peter Seibel * peter@xxxxxxxxxxxxxxx
Gigamonkeys Consulting * http://www.gigamonkeys.com/
Practical Common Lisp * http://www.gigamonkeys.com/book/
.

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