I would also change

print "bad type: $type"
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to

die "bad type: $type"
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just so you don't have to endure output like

bad type: letterbad type: letterbad type: letterbad type: letterbad ty
+pe: letterbad type: letterbad type: letterbad type: letterbad type: l
+etterbad type: letterbad type: letterbad type: letterbad type: letter
+bad type: letterbad type: letterbad type: letterbad type: letterbad t
+ype: letterbad type: letterbad type: letterbad type: letterbad type: 
+letterbad type: letterbad type: letterbad type: letterbad type: lette
+rbad type: letterbad type: letterbad type: letterbad type: letterbad 
+type: letterbad type: letter$
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