Create unique types from base types in TypeScript?

Question

I want to provide unique types of class objects, even if they are all strings. I tried to use type, and I tried to get a base class with unique subclass names.

See the following example. Neither typenor extendsdoes it allow me to instruct the compiler to treat them as unique types. I can still pass HumanId to a function waiting for AnimalId and vice versa.

I understand that they are compatible with objects, and this is because of the basic perspective of JavaScript, which makes the general sense. In fact, if I add a unique member to AnimalId, I will get the expected error:

Argument of type 'HumanId' is not assignable to parameter of type 'AnimalId'.

Is there a good approach with TypeScript to create unique type aliases for base types?

// type HumanId = string;
// type AnimalId = string;

class id {
    constructor(public value: string) { }
    toString(): string { return this.value;}
}
class HumanId extends id { };
class AnimalId extends id { };

function humanTest(id: HumanId): void {

}

function animalTest(id: AnimalId): void {

}

let h: HumanId = new HumanId("1");
let a: AnimalId = new AnimalId("2");

animalTest(h);

Answer 1

, . - .

, , :

class HumanId extends id {
  private _humanId: HumanId; // Could be anything as long as it is unique from the other class
}
class AnimalId extends id {
  private _animalId: AnimalId;
}