sub FETCH { return undef } works for defined($undef) and (tied $undef)->{exists} can store out of band properties.

I couldn't get this to round-trip with YAML, I guess special serialization code would be required, either using YAML::Node or some caller() checking kludge in FETCH.

Then deserializing would need another hack... nevermind

Brad

In reply to Re^2: Special undefs with attributes by bsb
in thread Special undefs with attributes by bsb

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