Given the unwieldlyness of exceptions, perhaps what I would really want in an OOP language is a construct to say "return from this function, AND the calling function, and return value X from the calling function.".
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This gets tricky when you consider different return types. This either requires that functions don't declare a return type, or that all of them return some kind of "result" type.
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You define a sum type with the possible errors and implement the From trait for implicitly converting from each. For example, #[derive(From)] enum MultipleError { One(ErrorOne), Two(ErrorTwo) }. You can use the ? operator (or the legacy try!) to return one of the variant types.
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By the way, I only linked the old 1.9 try! page because it's what came up at the top of the Google results. There are examples with the new built-in ? syntax rather than the legacy try! macro doing the same thing in the current page which I meant to link: doc.rust-lang.org/std/macro.try..
This C++ paper is also interesting in this regard - Zero-overhead deterministic exceptions: Throwing values open-std.org/jtc1/sc22/wg21
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Not trolling: once you've added this amount of syntax sugar, how is the Rust approach much different from checked exceptions?
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It doesn't involve invisible control flow through functions or unwinding. You can see every potential return directly in the source code. The syntactic sugar is very light was implemented as a macro, which can be user-defined too. The operator is just a short hand form of it.
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