Aurelia computed using an object

Question

I have an object statethat has a property session, this property can be either objector null.

I don't want to check getter dirty isSessionActive(), so I would like to use computedFrom(). However, it computerFrom()does not work when this object changes if it was not previously undefined.

Can I do this without a special isSessionActiveboolean property in 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

In the end, I just did the following:

isSessionActive: boolean = false;

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

Answer 2

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