Derive Macro KeyValuePair 

#[derive(KeyValuePair)]

Derives the KeyValuePair trait for a enum. Each variant need to have a value field which becomes part of the value enum and all remaining fields become part of the key.

Assuming the enum is called Abc it exposes AbcKey and AbcValue types for it too. The key enum will have Debug, Clone, PartialEq, Eq, and Hash derived. The value enum will have Debug and Clone derived. It’s expected that all fields implement these traits.