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Scala - Actors, or Back From Functional Programming to Object Oriented Programming

I started my Scala journey 7 years ago in a pragmatic way compared to the functional programming enthusiasts of nowadays (although a research lab made me program a media player using only XSLT — you can't get anymore functional than that!). At the time I had written a few Java programs of medium complexity and I often bumped into the limitations of object oriented programming.

Modeling everything as objects — with their promise of encapsulation — seems nice and tidy in theory but, as the size of the program grows, side effects create unforeseen interactions. I found it easier to reason in terms of immutable data and functions, which led me to write my programs in a more functional way over time.

Fast-forward to the present day and Scala has now become partly synonymous with Akka Actors which, with their message passing semantics and encapsulated internal state, are a new incarnation of object oriented programming.

Granted, it does not include inheritance and its associated pitfalls. On the the other hand,  messages are now asynchronous, which increases the complexity of a system quite a bit.

As a consequence of that, I'm wary of sending messages to a bowl of actor spaghetti. Is the promise of a new non-blocking RMI worth it?

There are other ways.

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