打字稿定义文件和扩展外部类型

Question

I'm trying to extend one of my own types from an external type.

Since I don't really know what I'm doing I am putting these in the global.d.ts file.

Previous to doing this I have been importing types into every typescript file in my project which seems wrong and messy (30 import lines on the top of every file).

global.d.ts file works when I just have my code in it

// successfully can use this anywhere
interface IPerson {
   name: string
}

Where my understanding stops is what if I have a type that needs to extend one that's external.

(For example I'm going to try to extend the Redux action type).

/// <reference path="../node_modules/redux/index.d.ts" />

interface IPerson {
  name: string
}

// even with the reference typescript 'cannot find name Action'
interface PersonAction extends Action {
   person?: IPerson
}

I can successfully get typescript to stop complaining that it can't find 'name Action' if I change the file to this

import * as Redux from 'redux';

interface IPerson {
  name: string
}

interface PersonAction extends Redux.Action {
  person?: IPerson
}

Except now every file that uses IPerson can no longer find it. I don't understand why. Anytime I add an import to a declaration file it breaks everything else, but fixes the declaration file.

What am I doing wrong here? I'm looking for a place I can put all my types, if there's a better way to get typescript to recognize my types I'm open to other options.

Answer 1

I think you need to export the interface from your module:

import * as Redux from 'redux';

export interface IPerson {
  name: string
}

export interface PersonAction extends Redux.Action {
  person?: IPerson
}

and then import the same at the place of usage:

import {IPerson, PersonAction} from 'your-module'

PS Though it is not a problem, you might want to loose the 'I' from the name of interfaces .