Differences

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--- at:tutorial:actors [2007/04/01 11:54] – finished tvcutsem
+++ at:tutorial:actors [2007/04/01 12:05] – added tvcutsem
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 === Asynchronous Message Sending ===
+AmbientTalk, like E, lexically distinguishes between synchronous method invocation and asynchronous message sending. The former is expressed as ''o.m()'' while the latter is expressed as ''o<-m()''. Regular object references can carry both kinds of invocations. Synchronous method invocation behaves as in any typical object-oriented language. When an asynchronous message is sent to a local object ("local" meaning "hosted by the same actor"), the message is enqueued in the actor's own message queue and the method invocation will be executed at a later point in time.
+Far references, like the reference stored in the variable ''a'' above, only carry asynchronous message sends, and as such totally decouple the objects in different actors in time: objects can //never// be blocked waiting for an outstanding remote procedure call, they can only communicate by means of purely //asynchronous// message passing. This is a key property of AmbientTalk's concurrency model, and it is a crucial property in the context of [[distribution|distributed programming]].
+Hence, given the example above, the method ''sayHello'' can only be invoked as follows given a far reference ''a'':
+<code>
+>a<-sayHello();
+>>nil
+</code>
+async messages, parameter passing, futures
 === Isolates ===
+isolate stripe, by-copy, scoping rules, no external method defs
 === Actor Mirrors ===
+explain: mirror factory, message creation, message sending, install
+=== Nesting Actors ===
+lexical scoping rules for nested actors