Are there problems using Try or Either to handle errors in the Scala open / open source API?

Question

I noticed that many Scala open source APIs use Future(like Slick) or Java-style exception handling (like spray-json) rather than Tryor Either.

Are there problems with reverting, Tryor Eitherin simple open source APIs that are not lengthy or asynchronous? Should I avoid these and, if so, what should I use instead?

(Obviously, I would rather use the basic Scala APIs rather than third-party libraries such as Scalaz, so as not to force downstream users to use these libraries.)

Answer 1

TryGreat for wrapping exceptions for non-asynchronous operations.
However, I believe that using an exception instance to return a non-exceptional error condition is incorrect. I also stick to this when the API is asynchronous and uses Future. Mixing exceptional errors with business errors easily leads to incorrect / insufficient error handling by API clients (otherwise me :)).

If you decide to use exceptions to indicate your business mistakes, remember that exceptions have a hidden price: building a stack trace. This can be facilitated if you create your own business exceptions and mix scala.util.control.NoStackTrace.

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Answer 2

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Answer 3

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