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at:tutorial:actors [2007/07/18 11:21] elisagat:tutorial:actors [2007/07/18 11:21] elisag
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 Blocking a thread on a future can be a major source of deadlocks, like any form of blocking, of course. In the actor paradigm where communication between actors should remain strictly asynchronous, this behaviour is obviously unwanted. Furthermore, in a distributed programming context, it is highly undesirable to make one actor block on a future that may have to be resolved by an actor on another machine. It would make the application much more vulnerable because of latency or partial failure, resulting in unresponsive applications at best, and deadlocked applications at worst. Blocking a thread on a future can be a major source of deadlocks, like any form of blocking, of course. In the actor paradigm where communication between actors should remain strictly asynchronous, this behaviour is obviously unwanted. Furthermore, in a distributed programming context, it is highly undesirable to make one actor block on a future that may have to be resolved by an actor on another machine. It would make the application much more vulnerable because of latency or partial failure, resulting in unresponsive applications at best, and deadlocked applications at worst.
  
-The solution proposed in the [[http://www.erights.org|E language]], and adopted in AmbientTalk, is to disallow direct access to a future by any object. Instead, objects may **only** send **asynchronous** messages to a future object. This enables the future to temporarily buffer such messages until its resolved value is known. The net effect of this solution is that futures actually can be "chained", forming asynchronous //pipelines// of messages, as will be further explained in the next section.+The solution proposed in the [[http://www.erights.org|E language]], and adopted in AmbientTalk, is to disallow direct access to a future by any object. Instead, objects may **only** send **asynchronous** messages to a future object. This enables the future to temporarily buffer such messages until its resolved value is known. The net effect of this solution is that futures actually can be "chained", forming asynchronous //pipelines// of messages, as will be illustrated in the next section.
  
 ==== Working with Resolved Futures ==== ==== Working with Resolved Futures ====
at/tutorial/actors.txt · Last modified: 2020/02/05 21:26 by elisag