You cannot change the value of hash keys. You can, however, do a delete and an insert: 
$this->{data}{them} = delete $this->{data}{$that->{name}};
$that->{name} = "them";

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It may of course be better to take a course of action where you don't duplicate data.

In reply to Re: Dynamic hash keys by JavaFan
in thread Dynamic hash keys by markdibley

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