Module structs 

Available on crate feature guide only.

Struct errors

You may not always need the flexibility of an enum for your error type. In those cases, you can use the familiar SNAFU attributes with a struct:

#[derive(Debug, Snafu)]
#[snafu(display("Unable to parse {value} as MyEnum"))]
struct ParseError {
    value: u8,
}

// That's all it takes! The rest is demonstration of how to use it.

#[derive(Debug)]
enum MyEnum {
    Alpha,
    Beta,
    Gamma,
}

impl TryFrom<u8> for MyEnum {
    type Error = ParseError;

    fn try_from(other: u8) -> Result<Self, Self::Error> {
        match other {
            0 => Ok(Self::Alpha),
            1 => Ok(Self::Beta),
            2 => Ok(Self::Gamma),
            value => ParseSnafu { value }.fail(),
        }
    }
}