Safe navigation operator (?.) or (!.) and null property paths

Question

In Angular 2 templates safe operator ?. works, but not in component.ts using TypeScript 2.0. Also, safe navigation operator (!.) doesn

Answer 1

Update:

Planned in the scope of 3.7 release
https://github.com/microsoft/TypeScript/issues/33352

---

You can try to write a custom function like that.

The main advantage of the approach is a type-checking and partial intellisense.

export function nullSafe
    (obj: T, k0: K0, k1?: K1, k2?: K2, k3?: K3, k4?: K4, k5?: K5) {
    let result: any = obj;

    const keysCount = arguments.length - 1;
    for (var i = 1; i <= keysCount; i++) {
        if (result === null || result === undefined) return result;
        result = result[arguments[i]];
    }

    return result;
}

And usage (supports up to 5 parameters and can be extended):

nullSafe(a, 'b', 'c');

Example on playground.