After reading S12<v58>, I have many many notes about things that need to be tightened up or places that open more questions then provide answers.

But, a lot of it boils down to a core set of issues. Can y'all explain these to me? Help me see the core concepts, and I can work out the details and submit draft text back for review. So consider answering this for me well as an investment <g>.

A method can refer to private attributes etc. in other objects than self. This is unlike Smalltalk and like C++. Which objects? Obviously, those that _have_ them in the first place. Does the variable used as the invocant, or return value if it is an expression, have to be statically typed as being of the identical class? Or does it apply that constraint implicitly at run-time? If the former, note that in C++ it must be the identical class, NOT a derived class, even though that is simple to work around, because that is a conceptual point.

If class C { has $.a; ... }, then I understand that members may refer to $.a directly but outside of the scope of members defined in the class they can only be reached by accessors, a() as a method call.

But, it is also stated that in derived and trusted classes, and even in the class itself, $.a is an accessor call? As opposed to $!a which is the direct access to the attribute. Is this accessor different from the function form used outside the class? Why keep the variable syntax?

I'm getting a picture of 3 forms of access: Really direct, direct but asking the class to access it rather than knowing how storage works, and indirect that may involve your own code to do other things besides just get/set the attribute. But I think the middle one can be handled invisibly by the compiler -- it's no different from a tied hash.

How private is private? I wonder if what you've called private things are really more like "protected" in C++ (accessible by the derived class) and that 'my' attributes are really private, as are submethods. It's all confused. Who is allowed to access what?

Meanwhile, I'm concerned about lvalue subs as rw accessors, but I'll table that for now.


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