Hmm, you think?

I’m currently engineering a system that uses an actor framework to describe graphs of concurrent processing. We’re going to a lot of trouble to set up a system that can inflate a description into a running pipeline, along with nesting subgraphs inside a given node.

It’s all in-process though, so my ears are perking up at your comment. Would you relax your statement for cases where flexibility is important? E.g. we don’t want to write one particular arrangement of concurrent operations, but rather want to create a meta system that lets us string together arbitrary ones. Would you agree that the actor abstraction becomes useful again for such cases?

> we don’t want to write one particular arrangement of concurrent operations, but rather want to create a meta system that lets us string together arbitrary ones. Would you agree that the actor abstraction becomes useful again for such cases?

Actors are still just too general and uncontrolled, unless you absolutely can't express the thing you want to any other way. Based on your description, have you looked at iterate-style abstractions and/or something like Haskell's Conduit? In my experience those are powerful enough to express anything you want to (including, critically, being able to write a "middle piece of a pipeline" as a reusable value), but still controlled and safe in a way that actor-based systems aren't.