fn unary_op_kind_for_token(&self, token: Token) -> WeldResult<UnaryOpKind> {
        let kind = match token {
            TExp => Exp,
            TLog => Log,
            TSqrt => Sqrt,
            TErf => Erf,
            TSin => Sin,
            TCos => Cos,
            TTan => Tan,
            TASin => ASin,
            TACos => ACos,
            TATan => ATan,
            TSinh => Sinh,
            TCosh => Cosh,
            TTanh => Tanh,
            _ => {
                return compile_err!("Invalid token for UnaryOp");
            }
        };
        Ok(kind)
    }
Helper function which returns the `UnaryOpKind` for a token.
weld/src/syntax/parser.rs