From Newsgroup: comp.lang.lisp

B. Pym wrote:

.. but now stuck on how to convert the "1001" string into a (1 0 0 1) integer list. Any help appreciated --- thanks!

an iterative solution:

(loop for digit across (write-to-string 9 :base 2) collect
(if (char= digit #\1) 1 0))

or a more functional solution:

(map 'list
#'(lambda (x) (if (char= x #\1) 1 0))
(write-to-string 9 :base 2))

Scheme:

(map string->number (map string (string->list "1001")))

(1 0 0 1)

Gauche Scheme

(map (cut - <> 48) (map char->integer (string->list "1001")))
--
[T]he problem is that lispniks are as cultish as any other
devout group and basically fall down frothing at the mouth if
they see [heterodoxy]. --- Kenny Tilton (05 Dec 2004)
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