connection.rs

pub struct HelloConnectMessage {
	salt: String,
	key: Vec<u8>
}

impl HelloConnectMessage {
	pub fn salt<'a>(&self) -> &'a String {
		&self.salt
	}
	
	pub fn key<'a>(&self) -> &'a Vec<u8> {
		&self.key
	}
}

impl Serializable for HelloConnectMessage {
	fn serialize(&self, _: &mut MemWriter) {
		//serialize
	}
}

#[msg_deserializer="3"]
pub fn deserialize_hello_connect(_: &mut MemReader, _: TypeFinder) -> Message {
	// deserialize
	let salt = String::new(); 
	let key = Vec::new();

	HelloConnect(HelloConnectMessage {
		salt: salt,
		key: key
	})
}

message.rs

pub enum Message {
	HelloConnect(HelloConnectMessage)
	// ...
}

sample.rs

fn main() {
	let reader = ...
	let id_msg = 3;
	let b = MessageBuilder::new();
	let message = b.parse(id_msg, reader);
	
	match message {
		HelloConnect(m) => println!("salt : {}", m.salt().as_slice()),
		_ => println!("unknown message")
	}
}