Why not just use autovivification? Replace all that code with: 
push @{$states{$data[0]}}, $data[1];

[download]
And let Perl handle the initial empty arrayref and subsequent lookup? What do you think this is, Java? {grin}

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: Better code for normalizing a list for a HoA? by merlyn
in thread Better code for normalizing a list for a HoA? by bradcathey

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