Code:Signature

A signature is a compact way of representing the types a function takes, and the types it outputs.

Form

Generally, a signature is of the form:

(arg1: Type1, arg2: type2, arg3: Type3, ... argN: typeN) -> ReturnType

With the name of the argument being separated from the type with a colon (:).

Modifiers

A type is not always on its own, sometimes it will have a modifier.

?

A question mark represents that an argument is optional, and doesn't have to be specified. For example, in the signature for rand-int:

(min: Number?, max: Number) -> Number

the argument min is optional. This means that we can leave it out, and call the function with either one or two arguments.

...

An ellipsis represents that a function takes zero or more of a given type. For example, in the signature for send-message:

(player: Player, messages: Any...) -> Unit

We must give the argument player, however after that, we can choose to put as many values as we want.

|

A pipe is placed inbetween two types, and denotes that it may be one type or another. For example, in the signature for player-by-name:

(name: String) -> Player | Unit

We see pipe being used. This means that this function could either return a Player or Unit.