带通用键的Typescript接口

Question

I am defining a api for a typescript frontend/backend application.

Now I want to write an interface that is allowed to contain all available keys defined in an other interface, prefixed with filter.

Lets say I have a user interface

interface User {
  firstname: string;
  lastname: string;
}

A User request can be filtered, so my general Request ist extended with FilteredRequest

interface FilteredRequest<T> {
  [key: 'filter.' + keyof T]: any;
}

Is this possible with typescript?

---

Ok because this is not possible right now.

Also not prefixing the key with someting does not work

interface FilteredRequest<T> {
  [key: keyof T]: any;
}

An index signature parameter type must be 'string' or 'number'.ts(1023)

But keyof is designed to return a string or number

Answer 1

Unfortunately this is not possible in the current (3.4.5) version of Typescript.

This feature is being debated on github issue.