Lightning components mandatory attribute errors

Question

We are iterating over a collection, which we set dynamically after invoking an Aura Controller. However, one of the elements of the collections has a undefined that gets mapped to a tab name, like so

  <aura:iteration items="{!v.myObjs}" var="obj" indexVar="index">
                <lightning:tab label="{!obj.Url__c}">

                </lightning:tab>
            </aura:iteration>

The following snippet fails if Url__c is undefined with the following error:

This page has an error. You might just need to refresh it.
Component.createComponentStack: invalid config. Expected component definition, found 'undefined'.
Callback failed:

It look long time for us to investigate and find out, is there a better way to handle the use case / visualize the error?

Answer 1

Lightning Expressions seem to follow JavaScript logic overall which means that you can use || as a makeshift null coalescing operator. So you could try as the binding expression:

{!obj.Url__c || 'Empty Label'}