Code correction suggestion : chats.components.ts

[mmazloum]

there is this peace of code in the tutorial (step 3) :
ngOnInit() { this.chats = Chats .find({}) .mergeMap((chats: Chat[]) => Observable.combineLatest( ...chats.map((chat: Chat) => Messages .find({chatId: chat._id}) .startWith(null) .map(messages => { if (messages) chat.lastMessage = messages[0]; return chat; }) ) ) ).zone(); }

I solved some erros in my code adding this minor details :
ngOnInit() { this.chats = Chats .find({}) .mergeMap((chats: Chat[]) => { return Observable.combineLatest( ...chats.map((chat: Chat) => Messages .find({chatId: chat._id}) .startWith(null) .map(messages => { if (messages) chat.lastMessage = messages[0]; return chat; }) ) )} ).zone(); }

infact just add a return on the Observable.combineLatest(...)

[corneezius]

For some reason, neither of these displays the chat.lastMessage in the view. Anyone else have this problem?

[adrprado]

Same problem as @corneezius. Also, can anyone explain this code, please? I know it tries to join both Chats and Messages collections, but... it's().kindOf().tooMuch(nested => isn't.it())?

    this.chats = Chats
      .find({})
      .mergeMap((chats: Chat[]) =>
        Observable.combineLatest(
          ...chats.map((chat: Chat) =>
            Messages
              .find({ chatId: chat._id })
              .startWith(null)
              .map(messages => {
                if (messages) chat.lastMessage = messages[0];
                return chat;
              })
          )
        )
      ).zone();