Macro type_def 

macro_rules! type_def {
    (unknown) => { ... };
    (bytes) => { ... };
    (object {$(unknown => $unknown:expr_2021,)? $($key:literal => $value:expr_2021,)+ }) => { ... };
    (array [ $($value:expr_2021,)+ ]) => { ... };
    (array { $(unknown => $unknown:expr_2021,)? $($idx:literal => $value:expr_2021,)+ }) => { ... };
    (array) => { ... };
}