Can a generic type be utilized to instantiate an object?

In my code, I have a class named Entity as shown below:

class Entity {
    constructor(readonly someValue: string) {}
    someFunction() {}
}

Now, I am trying to create a class that will handle these entities and be able to create instances of them. In order to allow for the possibility of deriving these entities in the future, I want to make the entity class a generic class argument like this:

class Manager1<T extends Entity> {
    create() {
        const instance = new T("theValue");  // ERROR: 'T' only refers to a type, but is being used as a value here.
    }
}

This results in the mentioned error. I also attempted another approach (which does not work either):

class Manager2<T extends new (someValue: string) => Entity> {
    create() {
        const instance = new T("theValue");  // ERROR: 'T' only refers to a type, but is being used as a value here.
    }
}

Is there a way to instantiate an Entity object inside the class, using only the TYPE as a generic argument (perhaps by enforcing that the constructor of that type must match the specified signature)?

Answer №1

In order to bring something into existence, you must provide a tangible object.
It is essential to have a real, physical entity as the basis for creation.

class Manager1<T extends Entity> {
    create(entityConstructor: new(v:string)=>T) {
        const instance = new entityConstructor("theValue"); 
    }
    
    owned: new(v:string)=>T
    constructor(owned:new(v:string)=>T){this.owned = owned}
    createOwned() {
        const instance = new this.owned("theValue"); 
    }
}

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