"When a class extends another class and utilizes properties within a static property, it essentially becomes

I have been encountering challenges with generics in TypeScript for quite some time now. My current setup is as follows:

First, there is a generic class defined as:

class Entity {  
    public static schema = {};
}

Then, there is a class that extends the generic class:

class User extends Entity {
    public static schema = {
       username: ""
    }
}

When I try to instantiate the class and use its parameters like this:

let user = new User();
user.username = "John Doe" //this does not work

I have experimented with using parameters and creating a generic type like:

type EntityType<T> = {
    [k in keyof T]: T[k];
};

However, I have struggled to make it function properly. I attempted using index signatures with interfaces and types but encountered numerous syntax errors and could not find a way to resolve them.

Are there any suggestions on how I can achieve this or something similar?

Answer №1

It appears that the method you are using to access the static property username is incorrect.
This results in it being declared in a different space.
Additionally, there seems to be confusion regarding the schema object where username is actually defined.

To properly access it, you should refer to it from the class itself:

User.schema.username

Alternatively, you can access it from an instance's constructor:

let user = new User()
user.constructor.schema.username

Keep in mind that the constructor is shared among all instances of the User class, including its static properties.
Therefore, each user will have the same name in your provided example.

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