return $hoa{$some_number}->[rand @{ $hoa{$some_number} }];
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But i'm not sure that it's an improvement

Thanks, FunkyMonk :) That's what I was looking for.

If you wanted a random element from a random array (which I think is what you're aiming at):

return do { my $arry = $hoa{ (keys %hoa)[rand %hoa] }; $arr->[ rand @$
+arry ] };
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Or possibly:

return $hoa{ my $key = (keys %hoa)[ rand %hoa ] }->[ rand @{$hoa{$key}
+} ];
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I can't think of a clean way to do it without some temporary or building a parallel data structure (containing either the indexes or a copy of all the elements).

Wow, is that a "my" declaration in the hash key? That's new to me, thanks :)

Maybe it's me, but your question is a bit confusing. Are you saying that $some_number would be the hash key that you want to get a random element from? As in, given $some_number = 20 you want to randomly get either "george" or "jane" or "elroy"?

You can certainly index into your HoA without line 6.

my $foo = $hoa{20}[1];  # assigns "jane" to $foo
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Yes, it's some kind of score that's used for the key.

my $count = do { # or keep track of it yourself while adding your elem
+ents to %hoa
 use List::Util qw/sum/;
 sum map ~~@$_, values %hoa;
};
sub randelt {
 my $i = int rand $count;
 my $v;
 while ((undef, $v) = each %hoa) {
  last if $i < @$v;
  $i -= @$v;
 }
 keys %hoa; # reset hash iterator
 $v->[$i];
};
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