...reminds me of another "make inheritance work" technique I'd heard of. Every object is a hash ref (as usual), but every class has their own key into it. Basically every object looks like the $corona in clinton's description. The Alter advantage over that method is mainly privacy.

No, the point isn't privacy, it's being out of band. The corona is attached as a piece of magic to the object which remains free to be anything. That keeps the actual object body uncommitted, a requirement for black-box inheritance.

Privacy is only secondary, its lack has never been a big deal in Perl OOP (or other Perl, for that matter). The problem isn't that one class can access another's data, the problem is that there is nothing else for it to access. Inside-out and Alter are different ways of addressing that problem.

Anno

In reply to Re^4: Beyond Inside-Out by Anno
in thread Beyond Inside-Out by Anno

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