Macro asn1_cereal::ber_choice_serialize

macro_rules! ber_choice_serialize {
    (_ { $rs_type:ident $this:ident $e:ident $writer:ident [$($items:ident, $tags:expr,)*] }
      [$($opts:tt)*] $item:ident, $inner:ty; $($args:tt)*) => { ... };
    (_ { $rs_type:ident $this:ident $e:ident $writer:ident [$($items:ident, $tags:expr,)*] }
      $item:ident, $inner:ty; $($args:tt)*) => { ... };
    (_ { $rs_type:ident $this:ident $e:ident $writer:ident [$($items:ident, $tags:expr,)*] }) => { ... };
    ($rs_type:ident, $($args:tt)*) => { ... };
}

Generate the BerSerialize implemention for an ASN.1 Choice type, represented by a Rust enum.