Functions

Declaration

fn Add(A: i32, B: i32) -> i32 {
    return A + B;
}

A function begins with fn. Parameter names precede types, and the result type follows ->. Omitting the result type means void.

Expression bodies

fn Square(X: f32) -> f32 => X * X;

An arrow body directly produces the expression's value for a non-void function.

Reference parameters

fn Inspect(Value: File&) { }
fn Update(Value: mut File&) { }

These fragments assume a File declaration. Reference access is read-only unless the type explicitly grants mut access.

Callable types

fn(i32) -> i32 describes a function value. ABI-qualified callable forms are a separate interoperability contract. An optional callable uses the ordinary optional type form; a callable address does not itself imply source-level nullability.