You asked for a perlish way, so here is it. (Or at least this is my idea of perlish.) (A lispish way would be a tail-recursive function.) 

use Data::Dumper; 
@arr= 1..18; 

(@{$aoa[@aoa]}[0..2], @arr) = @arr while @arr; 
$aoa= [@aoa]; 

print Dumper $aoa;

[download]

Update: hihi, I've just seen the sign under the post:

bottled water

In reply to Re: perlish mapping a list to triples by ambrus
in thread perlish mapping a list to triples by water

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