Is such a generic real in TypeScript?

Question

typescript

There is a function in which I pass the class:

function wrapper<T extends { start(...args: any[]): void }>(target: { new(...args: any[]): T }, ...args: any[]): T {
  let instance = new target();
  instance.start(...args);
  return instance;
}

Accordingly, you can do this:

class RandomClass {
  start(arg1: string, arg2: number) { /* ... */ }
}
let instance = wrapper(RandomClass, 'Hello, world!', 777);

But since I have it written , the code editor (for example, Visual Code) does not understand what arguments should go next, and I, as a programmer, have to think for myself which parameters I should pass. Is it possible to somehow rewrite the generic so that after I write the first argument to target, then subsequent arguments are taken from target.prototype.init? That is, if we return to the example above, so that after entering the code editor tells me that I should enter more . Is it even possible? Or is TypeScript not that flexible yet? target: { new(...args: any[]): T }, ...args: any[]
wrapper(RandomClass,arg1: string, arg2: number

Answer 1

Like this with arguments:

function wrapper<T extends { start(...args: unknown[]): unknown }>(target: { new(): T }, ...args: Parameters<T['start']>): T {
  let instance = new target();
  instance.start(...args);
  return instance;
}


class RandomClass {
  start(arg1: string, arg2: number) { /* ... */ }
}
let instance = wrapper(RandomClass, 'Hello, world!', 777); /// все ок
let instance2 = wrapper(RandomClass, 777); /// ошибка