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--- at:tutorial:actors [2007/04/07 20:20] – added tvcutsem
+++ at:tutorial:actors [2007/04/24 21:02] – added tvcutsem
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 So what exactly is a far reference to an object? The terminology stems from the E language: it is an object reference that refers to an object hosted by another actor. The main difference between regular object references and far references is that regular references allow direct, synchronous access to an object, while far references disallow such access. This is enforced by the kind of messages that these references can carry, as will be explained below.
+Note that, if the object referred to by a far reference is striped with one or more stripes, the far reference itself is striped with the same stripes. Hence, an object located on a remote actor can be tested for its stripes //synchronously//, there is no need to communicate with the remote actor, as the far reference itself includes stripe information.
 ==== Asynchronous Message Sending ====
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 If both the ''outer'' and ''inner'' actors lexically see ''x'', they could modify it concurrently, reintroducing race conditions on the internal state of an actor. Therefore, when defining an actor using a block of code, we disallow access to the enclosing lexical scope by the new actor. It is as if it was defined at top-level. Hence, actors behave similarly to [[#isolates|isolates]] in this respect. The above example is incorrect in that ''inner'' will not be able to read or modify ''x''.
-Recall that isolates could be given selective access to their enclosing lexical scope by creating a local copy of the variable. We allow actors to do the same. Hence, the above example can be written properly as:
+Recall that isolates could be given selective access to their enclosing lexical scope by specifying accessed variables as formal parameters to their initializing closure, which gave rise to copying the variable into the isolate. We allow actors to do the same. Hence, the above example can be written properly as:
 <code>
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 </code>
-Hence, it still makes sense to nest actors, but each actor will operate on its own local copy of the variable. Furthermore, the value bound to the copied variable is parameter-passed according to inter-actor parameter passing rules, so if ''x'' would be bound to an object, then ''outer'' would have a normal reference to the object, while ''inner'' would receive a far reference to the object.
+It still makes sense to nest actors, but each actor will have its own local copy of lexically shared variables. Furthermore, the value bound to the copied variable is parameter-passed according to inter-actor parameter passing rules, so if ''x'' would be bound to an object, then ''outer'' would have a normal reference to the object, while ''inner'' would receive a far reference to the object.