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POakka sending a closure to remote actor
 

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    <p><strong>Background</strong></p> <p>i want to send a closure to a remote actor. remote actor should run the closure on its data and send back the result. <em>May be it is not advisable, but for curiosity's sake that's i want to do now</em></p> <p>But i observe that if a closure is created as an anonymous function, it captures the outer object also and tries to marshal it, which fails if the outer object is not serializable, as in this case.</p> <pre><code>class Client(server: ActorRef) extends Actor { var every = 2 override def preStart() = { println("client started. sending message....") server ! new Message((x) =&gt; x % every == 0) } } </code></pre> <p>the above code generates exception while calling the remote actor. i could define a local variable in the method <code>preStart()</code></p> <p><code>val every_ = every</code> </p> <p>and use it in place of actor member variable. But i feel it is a workaround not a solution. and i will have to be very careful if the closure is any bit more complex.</p> <p>Alternative is to define a class inheriting from <code>Function1[A,B]</code> and send its instances as closure.</p> <pre><code>class MyFunc(every : Int) extends Function1[Int,Boolean] with Serializable { def apply(v1 :Int) : Boolean = { v1 % every == 0 } } server ! new Message(new MyFunc(every)) </code></pre> <p>But this separates the closure definition from the place it is used, and defeats the whole purpose of using a functional language. and also makes defining the closure logic more difficult.</p> <p><strong>Specific Query</strong></p> <p>Is there a way i can defer defining the body of the <code>Function1.apply</code> and assign the body of <code>apply</code> when i create the instance of <code>MyFunc</code> from a locally defined closure?</p> <p>e.g. </p> <pre><code>server ! new Message(new MyFunc(every){ // not valid scala code x % every == 0 }) </code></pre> <p>where <code>every</code> is a local variable?</p> <p>basically i want to combine the two approaches i.e. send an object of <code>Function1</code> over to remote actor with the body of <code>Function1</code> defined by an anon function defined in place where <code>Function1</code> instance is created.</p> <p>Thanks,</p>
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    1. COI guess you know what you are doing but I want to make sure you are aware that sending closures is considered a bad practice as clearly explained in the [documentation](http://doc.akka.io/docs/akka/snapshot/general/actor-systems.html) - paragraph Actor Best Practices alinea 3
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    2. COthanks for pointing it out. alternatively can i encapsulate that behavior in an actor and create it dynamically? i.e. dictate the behavior of the actor based on the closure rather than sending closure itself over to the actor.
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    3. COThere is a lot you can do but I have a feeling you are trying to implement the "wrong"/awkward solution to a specific problem. I believe if you edit your question and describe what you are trying to achieve, you will get better responses on SO
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