Reference Syntax

Immutable Reference ref

fn read(x: ref i32): i32
{
    return @x
}

fn main(): i32
{
    let value = 10
    print(read(ref value))
    return 0
}

Mutable Reference mut ref

fn inc(mut p: ref i32)
{
    @p = @p + 1
}

fn main(): i32
{
    let mut value = 10
    inc(mut ref value)
    print(value)  // 11
    return 0
}

Rules

Syntax	Semantics	Notes
ref value	Immutable shared borrow	Multiple allowed per statement
mut ref value	Mutable exclusive borrow	No overlapping allowed

Temporary Borrow Scope

Borrows are released at end of statement:

let r = ref value  // released after this statement

Parameter Passing

fn swap(mut a: ref i32, mut b: ref i32)
{
    let temp = @a
    @a = @b
    @b = temp
}