In the introduction, we executed some code:
Server is a class. We can tell it is a class because in SuperCollider, all class names start with capital letters. Nothing else may start with a capital letter.
local is a message. Supercollider uses a syntax called receiver notation, which looks like:
object.message(argument1, argument2, . . . argumentN)
Class.message(argument1, argument2, . . . argumentN)
The arguments are optional. So “Server.local” takes the class “Server” and passes the message “local” to it.
When we send a message to an object or a class, we get a return value. The object or class gives us something back. Often, but not always, what we get back is the object or class that we just sent the message to. Sometimes, however, we get back something else. Server.local returns an object that refers to the localhost server.
Server.local is a getter message. The Server class contains some data that belongs to the class rather than to any particular instance of the class. We can get at that data by using a getter message. Getter messages return data stored within an object or a class. Setter messages have a similar concept. They set a piece of data within an object or a class. We’ll talk about them more later.
We then take the result of Server.local (which is an object that refers to the localhost server) and send that object the message “boot.” Expressions are evaluated left to right, so Server.local.boot is equivalent to (Server.local).boot. An expression is a bit of code that returns a value. Server.local is an expression because it returns something. Server.local.boot is also an expression because it also returns something.
Server.local is not, itself, the localhost server, as that is a separate process. However, Server.local contains information about the localhost server. The object knows how to communicate with the Server via OSC. So when we tell it “boot”, it translates that for us into an OSC message and sends that message to the separate Server process.
- Class names must start with capital letters and are the only things that start with capital letters.
- We pass messages in receiver notation as object.message(argument) or Class.message(argument)
- Classes and objects return something when you send them messages.
- Getter messages return data stored within an object or a class.
- Expressions are bits of code that return something. They are evaluated from left to right.
- Server.local is an object which can do OSC communication for us.