Bah, all the solutions I have seen either violate the order not to create new lists, or seem to produce biased results. I think I have found a way to do neither.

Clearly, if we pick items randomly from the original list without replacement, we will generate a completely random ordering of the list. That is what the following code effectively does. 

my @a = (1 .. 10);
print join("\t", @a),"\n";
#starting from the end and working back
for ($i = $#a; $i > 0; $i--) {
    # pick a random guy to stuff in the ith slot
    $guy = int(rand($i + 1));
    #snatch the guy out, and stuff him in!
    splice(@a, $i, 0, splice(@a, $guy, 1));
}
print join("\t", @a),"\n";

[download]
It's a bit like pretending that we're making another list, but swapping things around using splice instead. Notice that the one guy that we never picked ends up as the first element in the array. Splice is cool.

In reply to RE: Randomize List of items by Alokito
in thread Randomize List of items by johannz

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