Why defining object method fails in TypeScript

Question

Why when I try to define object method:

export class Helper {
    function add(x: number, y: number): number {
        return x + y;
    }
}

I get following error:

Unexpected token. A constructor, method, accessor, or property was expected.

I followed example from this site: https://www.typescriptlang.org/docs/handbook/functions.html But when I remove function keyword it works, but that contradicts the official source.

Yoda · Accepted Answer · 2017-05-19 13:13:41Z

3

You should not use function inside a class! Change to it:

export class Helper {
    add(x: number, y: number): number {
        return x + y;
    }
}

Typescript doesn't allow functions as members of a class. So, change it to a method!

As said by mattjes, you could make the method static too...

export class Helper {
    static add(x: number, y: number): number {
        return x + y;
    }
}

Helper.add(1,2)

Yoda

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answered May 19, 2017 at 12:45

Bruno

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2 Comments

if you want it static just put static in front of the method declaration

No I don't want static(class) method,I want non-static(object) method.