Macro stomp_parser::frames

macro_rules! frames {
    { $group_name:ident,
        $(
            ( $name:ident, $command:ident, $origin:ident $(, $header_name:ident : $header_type:ident )* $(,( $(  $opt_header_name:ident : $opt_header_type:ident $(: $opt_header_default:tt)?),* ))? $(,[custom: $has_custom:ident])? $(,[body: $has_body:ident])? )
        ),+
    } => { ... };
}