https://doc.rust-lang.org/reference/items/enumerations.html#custom-discriminant-values-for-field-less-enumerations talks about "Custom Discriminant Values for Field-Less Enumerations", but does not mention at all that since https://github.com/rust-lang/rfcs/blob/master/text/2195-really-tagged-unions.md Rust also supports custom discriminant values and defined layout for enums with fields.