[E-Lang] marketing `inheritance', and "The Treaty of Orlando"

[zooko@zooko.com]

I've examined "The Treaty of Orlando" (although I haven't grokked it in its
fullness).


They appear to define *both* `delegation' and `inheritance' to mean that a method
invoked from within a method of the superclass (or parent object) is handled by the
subclass (or the child object).  This seems to contradict MarkM's assertion that
this distinction is essential to the common definition of `inheritance'.  


Here are the relevant parts:


The authors define a new word for a feature common to all O-O languages: `empathy',
which is new code "borrowing" methods or variables from old.  They write that this
"mechanism underlies both inheritance and delegation", and then they define
`empathy':

   We say that object A empathizes with object B for message M if A doesn't have
   own protocol for responding to M, but instead responds to M as though it were
   borrowing B's response protocol. A borrows just the response protocol, but
   not the rest of B. That is, any time B's response protocol requires a message
   to be sent to SELF (or a variable to be looked up), it is sent to A, not to
   B; otherwise, A and B respond in the same way.
   ...
   Formally, we say that object A empathizes with object B for M when the
   following holds: If B's behavior in response to M can be expressed as a
   function phi(B; M)--that is, B's method for M can be expressed as a function
   that takes SELF as an argument along with M--then A's response to M can be
   expressed using the same function as phi(A; M)--A's behavior is derived by
   using A wherever B would have used itself.

They then reiterate: "All incarnations of inheritance and delegation include
empathy; they differ as to when and how the relationships are determined."


Several times in _tToO_ they use a certain phrase to identify a kind of code re-use
that sounds like E to me -- they call it "dynamic inheritance".


I suggest that E be advertised as having "Dynamic Inheritance".


Regards,

Zooko

P.S.  Credit to Amber O'Whielacronx who, upon being presented with "the marketing
inheritance conundrum" this morning, immediately said "Why don't they call it
Something Inheritance?".