rotor::rotor_compose_state_machines!

macro_rules! rotor_compose_state_machines {
    (STRUCT_REPEAT $name:ident $context:ty [ $($name1:ident/$type1:ty)* ]
                               [ $($name2:ident/$type2:ty)* ]) => { ... };
    (SCOPE_STRUCT $name:ident $cursub:ident) => { ... };
    (SCOPE_WRAPPER $name:ident $context:ty [ { $cursub:ident $curtyp:ty } ]
                               [ $($subname:ident / $subtype:ty)* ]) => { ... };
    (SCOPE_WRAPPER $name:ident $context:ty
        [ { $firstsub:ident $firsttyp:ty } $( { $tail:ident $tailtyp:ty } )* ]
        [ $($name2:ident/$type2:ty)* ]) => { ... };
    (SCOPE_IMPL $name:ident $context:ty { $cursub:ident $curtyp:ty }
        $($subname:ident/$subtype:ty)*) => { ... };
    ($name: ident <$context:ty>  { $( $subname:ident($subtype:ty), )* }) => { ... };
}

State machine composition macros