Macro error_enum 

macro_rules! error_enum {
    ($enum_name:ident {
        $( $variant:ident$(($variant_type:ty))?),* $(,)?
    }$(,)?) => { ... };
}

Facilitates the creation of error enums with debug display

Example

use rs42::error_enum;

error_enum!(ErrorEnumName {
    Test,
    Data(u32),
    OtherTest,
});

let test = ErrorEnumName::Data(42);
assert_eq!(format!("{}", test), "Data(42)");
let test = ErrorEnumName::Test;
assert_eq!(format!("{}", test), "Test");
let test = ErrorEnumName::OtherTest;
assert_eq!(format!("{}", test), "OtherTest");

error_enum!(
    OtherErrorEnumName {
        Data(u32)
    },
);
let test = OtherErrorEnumName::Data(42);
assert_eq!(format!("{}", test), "Data(42)");