Right, that's the part where user input becomes code in my original post:

$dispatch_table{$tc} = sub {eval "tcid_$tc()"},
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$tc is a value entered by the user. I'm dynamically creating the sub name tcid_$tc based on that input. Since this is in an eval, there are of course bad things a user could do here (like supplying --tcid 1;<bad code here>), but since this code will never be released to the public I don't see this as a big issue. And of course I can add some additional parsing for example that a tcid is only \d+ and nothing else.