Aurelia's computedFrom with an object

Question

I have a state object which has a property session, this property can either be an object or null.

I don't want to have to dirty-check for the isSessionActive() getter, so I'd like to use computedFrom(). However, computerFrom() doesn't seem to fire when this object changes, unless it was undefined previously.

Can I do this without a dedicated isSessionActive boolean property on my state Store?

@autoinject
export class Home {
    firstName: string = "user";
    private state: State;

    constructor(private store: Store) {
       store.state.subscribe(
            response => this.state = response
       )
    }

    @computedFrom('state.activeSession')
    get isSessionActive() {
        return this.state.activeSession !== null;
    }
}

Answer 1

I ended up just doing the following:

isSessionActive: boolean = false;

constructor(private store: Store) {
    store.state.subscribe(
        response => { 
            this.state = response;
            this.isSessionActive = response.activeSession !== null;
        }
    )
}