[E-Lang] Hash Chaining & Capabilities, Proposal #2c: On-line RemoteEvaluation

[Mark S. Miller]

At 04:19 AM 10/25/00, Tyler Close wrote:

>> This has now been repaired.
>>
>http://www.erights.org/javadoc/org/erights/e/elang/evm/Evaluator.html
>is my
>> proposal for a remote evaluation service, and syntactic sugar to
>support it.
>
>I need to ask a stupid question before I can understand this.
>
>What is the difference between what the Evaluator is trying to
>accomplish, and what should happen when a Vat receives a pass-by-copy
>object of a type that it does not know yet?

A PassByCopy object of a previously remotely-unknown behavior also transmits 
the code for its definition, to be remotely evaluated.  However, the sender 
only has a hold of the local copy she sent, not the remote one, and not the 
remotely defined copy of the function for instantiating such objects.  The 
remote evaluation proposal gives the sender the ability to designate the 
results of evaluating code that she sent.

If passing a local PassByProxy object is an "over here", as in, the passed 
object remains with the sender and the receiver gets a remote pointer,

and passing a PassByCopy object is an "over here and over there", in that 
the object is local to both sides,

remote evaluation is "other there", in that the sender gets the remote pointer.


We may well be able to layer the mobile code aspect of PassByCopy on top of 
remote evaluation.