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What Result? Result is a generic not a specific type. It's essentially a shorthand instead of manually writing out the enum yourself.

More fundamentally I disagree that Either makes Result redundant. Result has semantic meaning that's lost with Either.




> What Result? Result is a generic not a specific type. It's essentially a shorthand instead of manually writing out the enum yourself.

No, it's not 'a generic', but it has generic type parameters. An enum can be any number of variants with any number of type parameters.

A result is: data Result a b = Err a | Ok b (or in Rust) enum Result<T, E> { Err(E), Ok(T) }

> It's essentially a shorthand instead of manually writing out the enum yourself.

I'm not sure which enum you're referring to. You do realise an enum can have any number of variants, not just 2? I could define a sum type with 16 variants. 'enum' is just Rusts keyword for defining sum types.

> Result has semantic meaning that's lost with Either.

Which is what?


> You do realise an enum can have any number of variants, not just 2?

Yes, that's what makes it more generic than Result. Indeed that's the only practical difference except for a few helper functions and a #[must_use] (which only makes sense for Result, not for a more general Either type).

>> Result has semantic meaning that's lost with Either.

>Which is what?

Seriously? Error checking! That's the whole point of it. One side has meaning over the other; it has weight. The "left" is the result you want. The "right" is when something gone wrong.


> Yes, that's what makes it more generic than Result. Indeed that's the only practical difference except for a few helper functions and a #[must_use]

I think you have some fundamental misconceptions about sum types. Note that enums also don't even need to have any variants.

enum Never {}

Either way, this discussion is no longer fruitful. I encourage you to read about sum & product types.




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