Re: sanity check (coding style)

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"))

(defun digest2string (v)
(with-output-to-string (s)
(loop for x across v
do (write-string (aref *hex-codes* x) s))))



--
Thomas A. Russ, USC/Information Sciences Institute

.

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