Those references were converted to strings, which means that you can't get your reference back by looking at keys. But the more important issue (to the OP) was that identical anonymous arrayrefs will not map to the same hash element. That is, each time you mention $HOR{[1,2,3]}, you're talking about a different element.
Caution: Contents may have been coded under pressure.

In reply to Re^2: Using references as hash keys by Roy Johnson
in thread Using references as hash keys by Ovid

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