Values are built-in object types. They can be created through literals, which are expressions that evaluate to a value. Values are immutable by default.

Booleans

There are two boolean literals, true and false.

true
false

Numbers

Oba uses double-precision floating point for all numeric values

0
1234
-1234
3.14159

Functions

Functions are first class values in Oba. They can be stored in variables and passed as arguments to other functions.

fn hello = system::println("hello")
fn call f = f()
call(hello)

Optional Values

Oba uses a built-in Data Type named Option to indicate the presence or absence of a value. The None constructor is used to signifiy the absence of a value, while the Some constructor is used to signify the presence of a value:

let none = None()
let some = Some("value")

system::println(none) // Prints: (Option::None)
system::println(some) // Prints: (Option::Some,value)
system::println(none == some) // Prints: false

The Option data type is visible to all Oba programs. It can optionally (ha) be imported from the “option” module:

import "option"

system::println(option::Some) // Prints: Option::Some