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  • Re: binary rep as list? string-to-list?

    From B. Pym@Nobody447095@here-nor-there.org to comp.lang.lisp on Mon Jul 14 19:32:26 2025
    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")))
    --
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