[racket-dev] How about adding this simple list-shuffling procedure to racket?

From: Carl Eastlund (cce at ccs.neu.edu)
Date: Thu Nov 11 12:18:29 EST 2010

On Thu, Nov 11, 2010 at 12:18 PM, Neil Toronto <neil.toronto at gmail.com> wrote:
> Eric Hanchrow wrote:
>> I find myself using this all the time; it seems it'd be handy to have
>> built in.
>> (define (shuffled list)
>>  (sort list < #:key (lambda (_) (random)) #:cache-keys? #t))
> Is the distribution of shuffled lists uniform? That'd be hard to analyze,
> since it would depend on the sorting algorithm. I would guess it's not.
> (Don't worry if you didn't catch this yourself. It's not exactly
> straightforward.)

It should be uniform regardless of algorithm, since #:cache-keys? is
#t.  Shouldn't it?


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