I'm not sure I understand your question completely, that's pretty abstract and terse.

But as far as I can tell you are tieing an object reference to control it's behavior when used like a nested data structure.

please note that you can also overload the dereferencing of the object's class for that effect.

dereferencing      => '${} @{} %{} &{} *{}',
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This should be cleaner and avoid any interference with tie's methods like FETCH, STORE, etc.

HTH! :)