Module-level constants allow the user to define fixed data that is shared across functions (or exported to be shared across modules). The syntax is simply:

const varname: typename = constvalue;
const othervar = otherconstval;

The typename is not required due to type inference, but can be added for clarity.

For those coming from Javascript/Typescript, const in Alan is much more strict. A constant is truly constant, not just a variable that can't be reassigned with a new struct. This means the following is invalid:

const pushedVals = new Array<int64> [ ];

fn saveForLater(val: int64) {

Shared mutable global state inherently prevents parallelization, so it is discouraged.