Can I send more than one variable in one port.emit?

Add-ons Development
#1

As I am working on a legacy extension in Addon SDK, can I send more than one variable in one emit message. All examples are based on one variable. If I want to pass more than one variable in one emit message, is this possible? what is the syntax?

var myMessagePayload = "some data";
self.port.emit("myMessage", myMessagePayload);
#2

You can put multiple values of arbitrary type in an Array and send that:

const string = 'foo', number = 42, object = { bar: 23, };
self.port.emit('myMessage', [ string, number, object, ]);

and receive them as

port.on('myMessage', ([ string, number, object, ] => { ... });
#3

Is this the right syntax? => ??
Because what I do is:

var myMessagePayload = "some data";
panel.port.emit("myMessage", myMessagePayload);

Then:

panel.port.on("myMessage", function handleMyMessage(myMessagePayload) {
  // Handle the message
});

If I have: myMessagePayload1 and myMessagePayload2. What is the right syntax to send and receive them because all the examples in the documentations show one variable. In SDK please.