使用前分配的变量 typescript

Question

Im using typescript for my next nodejs app, and I ran into the following problem. Here is my code:

class AuthService {
    public async init(req: Request, res: Response) {
        let user: IUser | null;
        const userId = res.locals.userId;
        if (userId) {
            user = await User.findById(userId);
        }

        return res.send({user}); // error here, as in the title
    }
}

I get the ts error: Variable 'user' is used before being assigned. What do i do wrong?

Answer 1

I guess the problem is that the value is only assigned to a variable when the if condition is met. So one of the solutions would be to assign it some value during declaration. Like let user: IUser | null = null;