Macro define_protocol 

macro_rules! define_protocol {
    (
        $(#[$meta:meta])*
        name: $name:ident,
        transport: $transport:expr,
        identify: |$data:ident| $body:expr
    ) => { ... };
}

Macro to define a new protocol by implementing the RefractiumProtocol trait.

This macro simplifies the creation of simple protocols that identify themselves by checking a data slice against a condition.