It is essentially equal to:

Barfoo::thisone($fb);
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Changing the call to that, and changing the name of the variable $self to something like $object won't change anything, but will make the code more readable, as well as making your intent more clear.

To me it seems you want a class method (as opposed to object method), or call it a function, that gets some information out of an object.

Does it need to be a real object at all? A hashref

$fb = { cow => 'moo' };
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would give the same result if you don't need more stuff (like methods) inside Foobar.

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