How to make a generic parent constructor that accepts object with keys of child class?-CodePudding

I'd like to make a base class that defines a constructor that allows all the keys of the child class to be passed, but this is unavailable in constructors. Here's what I'd like to achieve:

class BaseClass {
  constructor(props: {[key in keyof typeof this]?: typeof this[key]}) {
    Object.assign(this, props)
  }
}

class User extends BaseClass {
  name: string;
  age: number;
}

const user = new User({name: "John"});

But this errors with:

test.ts:2:60 - error TS2333: 'this' cannot be referenced in constructor arguments.

2   constructor(props: { [key in keyof typeof this]?: typeof this[key] }) {

Is there a way to achieve this? I'm not satisfied with any solutions where I have to supply any information about the child classes in the parent class' constructor.

CodePudding user response：

As you noticed, it is currently not allowed to use the polymorphic this type in constructor parameters. There is an open feature request for such support at microsoft/TypeScript#38038. It's open and marked as "awaiting more feedback", so anyone who is interested in seeing this happen might want to go there, give the issue a