Re: Given string 'a.bc.' -- replace each dot(.) with 0 or 1

* HenHanna <v2irh1$ndjr$2@dont-email.me> :
Wrote on Tue, 21 May 2024 12:09:22 -0700:

On 5/19/2024 11:36 AM, Joerg Mertens wrote:

HenHanna <HenHanna@devnull.tb> writes:
>

How can i write this function simply?   (in Common Lisp)
>
-- Given a string  'a.bc.'   -- replace each dot(.)  with 0 or 1.
>
        -- So the value is a list of 4 strings:
                                  ('a0bc0'  'a0bc1'  'a1bc0'  'a1bc1')
>
-- The order is not important.
             If the string has 3 dots, the value is a list of length 8.
>
If the program is going to be simpler,
                       pls use, e.g.   (a $ b c $)  rather than  'a.bc.'

>
>

Another one:
(defun subst-dots (s &optional (pos 0))
   (let ((p (search "." s :start2 pos)))
     (if p
(append
(subst-dots (replace (copy-seq s) "0" :start1 p) (1+ p))
(subst-dots (replace (copy-seq s) "1" :start1 p) (1+ p)))
(list s))))
Regards

Nice... Thanks

so my response to Steve in <m3bk52kmfu.fsf@leonis4.robolove.meer.net> :
on [Sun, 19 May 2024 18:06:53 +0530] where I said "Substitute doesn't
help here" was wrong. You can use SUBSTITUTE here like this

(defun subst-dots (s &optional (pos 0))
   (let ((p (search "." s :start2 pos)))
     (if p
(append
(subst-dots (substitute #\0 #\. s :start p :count 1) (1+ p))
(subst-dots (substitute #\1 #\. s :start p :count 1) (1+ p)))
(list s))))


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