Re: avoid narrow-to-region (was: Re: replace-regexp)

[Emanuel Berg via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>]

> Let's do it like this, if we can get the algorithm to work
> on an arbitrary list, then all data-type issues can be
> solved easily, by adding two functions, one disassembly
> function that splits the data into a list, and one assembly
> function that puts it back together, after the algorithm has
> randomized it!
>
> So for example if the data is the string "data":
>
> 1. "data" -> '("d" "a" "t" "a")
> 2. run the algorithm, get e.g '("a" "d" "t" "a")
> 3. '("a" "d" "t" "a") -> "adta"
>
> Because Lisp is already based on the universal data
> structure which can express all human knowledge, isn't it
> possible that there is already a Lisp list randomizer that
> fulfills even Yuri's most uncompromising demands?

What about this?

;; https://stackoverflow.com/a/49505968

(require 'cl-lib)

(defun nshuff (sq)
  (cl-loop
     for i from (length sq) downto 2
     do (cl-rotatef (elt sq (cl-random i))
                    (elt sq (1- i)) ))
  sq)
  
;; (nshuff '(a b c)) ; (b c a) (a b c) (b c a) ...

Shufflepuck Café!

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