When you say 
$bits{'one'}=@test;

[download]
you are really giving @test scalar context. That's why $new[0] the second time returned 3 - that's the number of elements in @test. Basically, you can't just lay these data structures on top of each other.
Try using a reference and dereferencing later: 
my @test = ( qw / bing bong bang / );
print '['.$test[2].'] ['.$test[1].'] ['.$test[0]."]\n";
$bits{'one'}= \@test;
my @new =  @{$bits{'one'}};
print '['.$new[2].'] ['.$new[1].'] ['.$new[0]."]\n";

OUTPUT:
[bang] [bong] [bing]
[bang] [bong] [bing]

[download]
\@test is a reference to test, and  @{$bits{'one'}} accesses the reference ($bits{'one'}) and the @{} dereferences it. Have you tried perlreftut?


UPDATE:
Coruscate reminded me of one of my favorite methods of array reference that I forgot to mention - [@test]. Trust me, all the cool kids are doing it. I hear it's all the rage in Japan. Even though it isn't exactly the same as \@test, for your purposes it works the same.
UPDATE 2:
sauoq has a good point. Chatterbox discussion showed that in fact @{$bits{'one'}} = @test is much faster than [@test] and /@test anyway. Check out my pad for benchmarking details.

In reply to Re: A hash of lists by jweed
in thread A hash of lists by wolis

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