I agree with Heiko on this one - import context.dispatcher is used 
everywhere. It is mentioned in the docs not to close over 'context' and 
access it outside of message handlers, however I think more education is 
needed here. 

On Wednesday, March 7, 2018 at 5:35:05 PM UTC-8, Konrad Malawski wrote:
>
> Yes it is nulled using unsafe.
>
> -- 
> Cheers,
> Konrad 'ktoso <http://kto.so>' Malawski
> Akka <http://akka.io/> @ Lightbend <http://lightbend.com/>
>
> On March 8, 2018 at 7:32:56, Heiko Seeberger (loe...@posteo.de 
> <javascript:>) wrote:
>
> `import context.dispatcher` is what „everybody“ is doing, not? I’m using 
> it all over the place, because I have learned that one can import from 
> stable identifiers (e.g. vals) in Scala. Hence I don’t think changing the 
> docs has the necessary effect.
>
> How can a final val be „nulled"? Unsafe? Reflection?
>
> Cheers
> Heiko
>
> --
>
> Heiko Seeberger
> Home: heikoseeberger.de
> Twitter: @hseeberger
> Public key: keybase.io/hseeberger
>
>
>
>
> Am 07.03.2018 um 19:23 schrieb Patrik Nordwall <patrik....@gmail.com 
> <javascript:>>:
>
> Thanks!
>
> On Wed, Mar 7, 2018 at 6:16 PM, Jeff <jknigh...@gmail.com <javascript:>> 
> wrote:
>
>> An example of documentation for using import context.dispatcher is here 
>> https://doc.akka.io/docs/akka/2.5/futures.html#within-actors 
>>
>> I can create some PR to update the documentation
>>
>> On Wednesday, March 7, 2018 at 6:09:24 AM UTC-8, Patrik Nordwall wrote: 
>>>
>>> It's because when the actor is stopped some of the fields are cleared 
>>> (yeah, even though they are vals) to "help" the GC in case something (e.g. 
>>> an local ActorRef) is still referencing the actor instance. 
>>>
>>> implicit val ec = context.dispatcher
>>>
>>> would solve it here.
>>>
>>> Where in the documentation is the import recommended? We should probably 
>>> update that. Would you be able creating a PR fixing it? Thanks.
>>>
>>> /Patrik
>>>
>>> On Tue, Mar 6, 2018 at 10:44 PM, Jeff <jknigh...@gmail.com> wrote:
>>>
>>>> I suspected as much. So what would you suggest as for handling use 
>>>> cases where you could have chained flatmaps on futures that at the end 
>>>> will 
>>>> pipeTo a message back to the actor. Should we set the ExecutionContext to 
>>>> a 
>>>> val? 
>>>>
>>>> On Tuesday, March 6, 2018 at 12:09:22 PM UTC-8, √ wrote: 
>>>>>
>>>>> Context is bound to the lifecycle of the actor.
>>>>>
>>>>> On Tue, Mar 6, 2018 at 8:37 PM, Jeff <jknigh...@gmail.com> wrote:
>>>>>
>>>>>> I have noticed an issue where if a future maps/flatmaps after actor 
>>>>>> shutdown, a NullPointerException is thrown. I've narrowed it down to 
>>>>>> the import context.dispatcher, which I technically understand since 
>>>>>> that is closing over actor state. If I change that to implicit val 
>>>>>> ec = context.dispatcher, everything works fine.  
>>>>>>
>>>>>> I'd like to understand what is the best practice in this case, since 
>>>>>> the documentation for context.dispatcher indicates that it is 
>>>>>> threadsafe and looking at the actor trait, context is a val. Most 
>>>>>> documentation seems to indicate that import context.dispatcher is 
>>>>>> preferred. 
>>>>>>
>>>>>> Thanks
>>>>>> Jeff
>>>>>>
>>>>>> --
>>>>>> >>>>>>>>>> Read the docs: http://akka.io/docs/
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>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Cheers,
>>>>> √
>>>>>
>>>>
>>>> --
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>>>
>>>
>>>
>>> --
>>>
>>> Patrik Nordwall
>>> Akka Tech Lead
>>> Lightbend <http://www.lightbend.com/> -  Reactive apps on the JVM
>>> Twitter: @patriknw
>>>
>>>
>> --
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>
>
>
> --
>
> Patrik Nordwall
> Akka Tech Lead
> Lightbend <http://www.lightbend.com/> -  Reactive apps on the JVM
> Twitter: @patriknw
>
>
> --
> >>>>>>>>>> Read the docs: http://akka.io/docs/
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-- 
>>>>>>>>>>      Read the docs: http://akka.io/docs/
>>>>>>>>>>      Check the FAQ: 
>>>>>>>>>> http://doc.akka.io/docs/akka/current/additional/faq.html
>>>>>>>>>>      Search the archives: https://groups.google.com/group/akka-user
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