Affine types / ownership system

It would be amazing if typescript could gain types with an ownership semantics as it could provide a very powerful tool against bugs caused by mutations. Idea is inspired by Rust's owneship system and adapted to match ts / js language. Idea is to provide built-in types for which move semantics would be tracked. In the example below I'll refer to that type as Own<t>

Ensures that there is exactly one binding to any given Own<t>, if it is assigned to another binding type of the former binding should become Moved<t> and type of the new binding should be Own<t>.

const array:Own<number[]> = [1, 2, 3]
const array2 = array // => <Own<number[]>> [1, 2, 3]
const first = array[0] <- [TS]: `Moved<number[]>` has no index signature.

A similar thing should happens if function is passed Own<t>, binding in the caller scope will get type Moved<t>:

function take(array: Own<number[]>) {
    // What happens here isn’t important.
}

let array:Own<number[]> = [1, 2, 3];

take(array);

array[0] // <- [TS]: `Moved<number[]>` has no index signature.

Rust also has also borrowing semantics which may be also worse pursuing. But for now I'm going to leave it out until I get some initial feedback.

Why

Typescript already provides tools to deal with the same class of issues using readonly feature, which is nice but mostly useful with immutable data structures that do impose an overhead. With an ownership system it would be possible to author performance critical code without an overhead while still maintaining safety guarantees from the type system.

提案されている Own と Moved の例から始め、TypeScript に既存の readonly 機能と比較してください。この issue ではソースファイル、エントリポイント、テストが指定されていないため、まず代入と関数引数の型チェックがどこに実装されているかを特定してください。ownership と move のルールが一貫してテストできるだけ十分に仕様化されれば完了です。