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andiderp hat geschrieben:Should the lights turn off after a specific amount of time?

create a timer with a delay of 100ms

I will try to give a hint without spoiling the solution:

Try to think about what the method from the stackable traits example would be in your case.
When do you want to run your code in e.g. FireAlarm? Probably after "constructing" your house...

Our motion detectors only report the position where they have sensed any motion last. This means, that the motion detectors don't report the time, when motion was detected, but only where motion was detected (the position). In this task you are supposed to turn on the lights when there was movement...

=> String means that this parameter is passed by name . The following quote nicely summarises the difference: A parameter of type A acts like a val (its body is evaluated once, when bound) and one of type => A acts like a def (its body is evaluated whenever it is used). More details on this topic ca...

Yes. That's no problem...

Also these errors suggest, that something in the compiler got seriously messed up. Also it seems that you are using IntelliJ and there might be a problem with its incremental compiler. To be on the safe side run sbt clean and then sbt compile on the commandline to check that its not a problem with i...

OK. So the Scala compiler does continue to compile even after errors, but errors might still "chain", so one error might cause others until the Scala compiler stops.

Fix the first error that appears first, and the other errors might "fix" themselves.

Are there any other errors (especially might there be some in PerfSpec.scala)? Without seeing the code, I can otherwise not really tell what the problem might be. If you fail to determine the cause, you might DM me your current implementation and I can take a look.

Can you supply me with the complete sbt compile error message?

Looking at your current implementation, the issue is really the type signature of the serialize and deserialize methods. In your case the problem is more subtle though. You import import java.lang.Long . Without importing this, Long will default to the Scala version of a long. By using your import, ...

Please DM me your implementation of your trait Serializer.

The purpose of this task is not clear to me. Just writing some test objects with some combination of traits and a dummy call to measure are not that enlightening. In fact this only shows that objects with some combinations of the stackable traits are runable. To really use the framework one would n...

On a first look, I would say, that you changed the signatures of serialize and deserialize in the Serializer trait, which you should avoid.

There will be no exercise on 22.11.

That should depend on which traits are mixed in. The user should be able to decide...