You can trim your shuffle a little by omitting the line:         next if $i==$j;.

Swapping an item with itself doesn't affect the algorithm's fairness, and doing it once costs less, than testing n times and avoiding it once.

And you save a little more by avoiding the list assignment: 

my $tmp = $array[ $i ]; 
$array[ $i ] = $array[ $j ]; 
$array[ $j ] = $tmp;

[download]

Doesn't look as nice though.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re^3: mem usage by BrowserUk
in thread mem usage by halfcountplus

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