Macro repr_bound 

macro_rules! repr_bound {
    (
        // e.g. `pub MyReprs<T: Foo + Bar> [ Spam<T>, Eggs ]`
        $vis:vis $repr_traits:ident
        $(<
            $($gen:tt $(: $b:tt $(+ $bs:tt)* )? ),+
        >)?
        [
            $($msg:ty),+
        ]
    ) => { ... };
}

The repr_bound macro creates a type alias that can be used as bound for the generic wire type, instead of listing all messages used by the protocol.

Example

#![feature(trait_alias)]

use async_session_types::*;

struct Foo(pub u8);
struct Bar(pub String);

repr_bound! { FooBarReprs [Foo, Bar] }

type Server = Recv<Foo, Send<Bar, Eps>>;

fn server<R: FooBarReprs>(c: Chan<Server, (), R>) -> SessionResult<()> {
    unimplemented!()
}

Note that there’s no comma after the last item!

Requires #![feature(trait_alias)].