Along the lines you mentioned, this works:

   my @shuffled = map { $_->[0] }
                  sort { $a->[1] <=> $b->[1] }
                  map { [ $_, rand() ] }
                  @unshuffled;

[download]

But compared to other approaches it is slow and memory-expensive.

This topic came up at a recent kw.pm meeting, and I played around and did some rudimentary benchmarks:

http://kw.pm.org/wiki/index.cgi?ListShuffle

2005-04-02 Janitored by Arunbear - replaced pre tags with code tags, to allow code extraction

In reply to Re^2: Is this a fair shuffle? by Anonymous Monk
in thread Is this a fair shuffle? by Roy Johnson

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