Ownership

Instances are owned by whatever scope they get assigned into. If their scope ends, they also end.

This instance doesn't get stored in memory because it isn't assigned anywhere:

new [score = 0]

This instance gets stored in memory in the global scope:

let player = new [score = 0]

This player instance gets stored in the function's scope, and then is lost when the function ends:

let createPlayer = [] -> {
    let player = new [score = 0]
}

Transfer

You can transfer ownership of an instance by re-assigning it to something else.

This player instance gets stored in the global scope because it gets assigned into the globally-scoped players instance.

let players = new [?]
let createPlayer = [n] -> {
    let player = new [score = 0]
    players.(n) = player
}

This also works with returning. This player instance continues to exist after the function call because it gets assigned into the globally-scoped playerOne.

let makePlayer = [] => {
    let player = new [score = 0]
    return player
}
let playerOne = makePlayer()

Reference

You can assign a reference of an instance with the @ character. This doesn't transfer ownership.

This stores a reference of the player instance inside playerOne. The true ownership of the instance is stored in players.

let players = new [?]
let createPlayer = [n] => {
    let player = new [score = 0]
    players.(n) = player 
    return @player
}

let playerOne = createPlayer(1)