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A comment on Using enums to represent state in Rust. Parent comment

Re:Using enums to represent state in Rust by twic on Friday September 22, 2023 @01:43PM (#37615126)
Rust enums always have a discriminant: https://doc.rust-lang.org/std/mem/fn.discriminant.html

Their representation in memory may not use it, but it's still defined.

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Re:Using enums to represent state in Rust by 0x457 on Friday September 22, 2023 @02:37PM (#37615902)
They do, but IIRC this mostly to compare enum variants when it can't implement `Eq` and/or `PartialEq`. For example, in tests.

There are also zero variants enums that don't have any discriminant, but still could be used.

I'm not sure what's the point of comparing it to C because enums in C only carry tags and no data, while unions only carry data and no tag. Enums in rust could do both.

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