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> If python was able to reliably tell you possible exceptions

I know typed errors in Java are regarded by many as a failure... but it is still conceptually very appealing to me.

I love result types and pattern matching in more typed/functional languages, except that they often have similar issues to go re: not having a stack trace.

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I liked checked exceptions, but higher-order functions break them. The method signature of stream.map(f) allows a generic type for f but it can't vary with f's exceptions. The choices usually boil down to "only throw unchecked exceptions" (like Runnable) or "throw any exception" (like Callable).

It’s worth noting that this is specifically a shortcoming of Java’s type system and not an unsolvable problem. I’m a fan of Swift’s solution where you can directly mark a function as only rethrowing errors from a given parameter; it’s a lot simpler than making the error type a full fledged type parameter and covers most scenarios.

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