How to define a private property when implementing an interface in Typescript?

Question

I\'m using TypeScript in my project and I have come across an issue. I\'m defining an interface like this:

interface IModuleMenuItem {
    name: string;
}
         


        

Answer 1

Use abstract classes instead.

Composition over inheritance.

interface AppInterface {
   app: express.Application
   port: string | number
}

abstract class AbstractApp implements AppInterface {
    app: express.Application
    port: string | number
    constructor(){
        this.app=express()
        this.port=8080
    }
    
    protected defaultMiddlewares(): void {}
}     

class App extends AbstractApp {
    constructor() {
        super()
    }

    protected defaultMiddlewares(): void {
        this.app.use(express.json())
    }
}