use std::fmt::Display; #[derive(Debug)] pub enum Error { DuplicateAttrsKey { key: String, }, TypeError { expected: &'static str, actual: &'static str, }, } impl Display for Error { fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { writeln!(f, "{:?}", self) } } pub type EvalResult<T> = Result<T, Error>;