simple object model (was: [self-interest] selfing Self)

[Steve Dekorte]

Jecel Assumpcao Jr wrote:
>   1) base level: objects look like menus, morphs, strings, etc...
>
>   2) reflective level: objects look like hash tables (or collections of
> slots)
>
>   3) implementation level: you have the actual memory format of objects
> with tricks such as "maps" to help make cloned objects smaller

> What I am investigating here is the possibility of bringing levels 2
> and 3 closer together (ideally level 2 would be a slightly "sugar
> coated" version of level 3).

I'm not sure what you mean here.
If you mean:
  1) method invocation
  2) reflection
  3) object model

Then scripting languages like python and lua unite the first 2:

1) table.slotName() = call the returned function

2) a = table.slotName (get slot value, be it a function or data)
     table.slotName = b (set slot value to data or function)

And Lua brings 3 (the implementation of the object model) up to the 
level of 1&2 (the language itself) by providing "hooks" that let you 
define what happens when a table lookup fails:

function index(table, slotName)
   local parent = rawgettable(table, "_parent")
   if parent then return parent[slotName] end
   error("object "..tostring(table).." has no slot 
named:"..tostring(slotName))
end

You can likewise define the clone method, so you're free to do things 
like NewtonScript style slot creation on write if you like, to conserve 
memory and instantiating time at the expense of slot lookup time.

It doesn't get much more "light-weight" than this.

Steve
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