Angular2 tutorial with VS2015 may encounter a call-signature error that is expected

Question

Angular2 tutorial with VS2015 may encounter a call-signature error that is expected

Currently following the Angular2 tutorial in VS2015 and encountering an issue with a warning that is impeding the compilation of one of my TypeScript files. The link to the tutorial is provided below.

https://angular.io/docs/ts/latest/tutorial/toh-pt4.html

The warning specifically mentions code typedef with the message expected call-signature: 'getHeroes' to have a typedef.

import { Injectable } from "@angular/core";

import { HEROES } from "./mock-heroes";

@Injectable()

export class HeroService {
    getHeroes() {
        return Promise.resolve(HEROES);
    }
}

I've tried researching but haven't come across any explanations that I could understand since I'm still relatively new and learning...

Could someone please assist me in altering the TypeScript code above to define the return type for the Promise returned by the getHeroes method?

typescript angular

Answer 1

Answer №1

After some trial and error, I was able to solve the issue by importing the Hero module and specifying the return type of the function as a Promise.

import { Injectable } from "@angular/core";

import { HEROES } from "./mock-heroes";
import { Hero } from "./hero";

@Injectable()
export class HeroService {
    getHeroes(): Promise<Hero[]> {
        return Promise.resolve(HEROES);
    }
}

Answer 2

After some trial and error, I was able to solve the issue by importing the Hero module and specifying the return type of the function as a Promise.

import { Injectable } from "@angular/core";

import { HEROES } from "./mock-heroes";
import { Hero } from "./hero";

@Injectable()
export class HeroService {
    getHeroes(): Promise<Hero[]> {
        return Promise.resolve(HEROES);
    }
}

Angular2 tutorial with VS2015 may encounter a call-signature error that is expected

Answer №1

Similar questions

Guide on passing LOCALE_ID from an observable within Angular 2

What is the best way to merge imported types from a relative path?

Using an array of functions in Typescript: A simple guide

Iterating through elements within the ng-content directive in Angular using *ngFor

What could be causing the "no exported member" errors to appear when trying to update Angular?

Toggle visibility of layers in ngx-mapboxgl

Having difficulty in dynamically loading an image from an API's URL in Angular

Instead of relying on the valueChanges method, consider using setValue or patchValue in Angular 4 to monitor

A warning has been issued: CommonsChunkPlugin will now only accept one argument

When utilizing the navigation.navigate function, react-navigation v6.0 may present an error message

How to utilize the CSS hover feature within an Angular directive?

Leveraging Angular 2 and Typescript for crafting a cutting-edge Chrome application

TypeScript purity - "The variable exports is not defined"

Is there a way to access Validators directly from the formControl?

Tips for effectively integrating an admin panel into an Angular project

The karma Jasmine test failed to invoke the async callback within the timeframe set by the jasmine.DEFAULT_TIMEOUT_INTERVAL

Struggling to effectively organize data routing within Angular? Let's tackle the challenges of

Bringing TypeScript modules from a local module into a React application

Retrieve the content text while handling errors using RxJs

Avoid activating automatic save feature in Material UI data grid