Macro dynsequence::dyn_sequence
macro_rules! dyn_sequence { [$t:ty | $r:expr => { $( $m:ident ($e:expr ) $(@ $i:expr)?; )* } ] => { ... }; [$t:ty => $($e:expr),*] => { ... }; }
macro_rules! dyn_sequence { [$t:ty | $r:expr => { $( $m:ident ($e:expr ) $(@ $i:expr)?; )* } ] => { ... }; [$t:ty => $($e:expr),*] => { ... }; }