If an instance attribute is to ever have any value, then it is at best: write-once.

I've never heard people say constants are write-once rather than read-only, yet the same applies to them.

Yes, I did say "read-only" attributes are «more "write-once" than "read-only"» earlier, but I now think that was a mistake.

Actually, Perl's constants are per-package rather than per process.

For each definition of an attribute, there is one value per object.

For each definition of a constant, there is one value per processinterpreter.

I have no idea what you think is per package.

In reply to Re^4: Psychic Disconnect and Object Systems by ikegami
in thread Psychic Disconnect and Object Systems by John M. Dlugosz

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